with tandem scroll compressors - dunham-bush … · with tandem scroll compressors ... 23 2.5.4...

Form No. 6109BJanuary 2004

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ACDS-B/AUDS-B

Air-Cooled Chillers

with Tandem Scroll CompressorsACDS-B/AUDS-B 015S-100DInstallation, Operation &Maintenance Manual

2

TABLE OF CONTENTS ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

Page

1.0 General Information1.1 Introduction................................................................................................................................ 5

1.2 Product Identification ............................................................................................................... 51.3 Physical Specifications - English I.P. and S. I. Units .................................................................. 6-9

2.0 Installation2.1 General Installation Instructions ............................................................................................... 10

2.2 Inspection.................................................................................................................................. 10

2.3 Handling, Storage and Rigging.................................................................................................. 10

2.3.1 General Handling Instructions ........................................................................................................... 102.3.2 Storage ............................................................................................................................................. 102.3.3 Rigging and Moving ......................................................................................................................... 10

2.3.3.1 Rigging Instruction Drawing ............................................................................................ 10

2.4 Space and Clearance Requirements2.4.1 General Space and Clearance Requirements ....................................................................................... 112.4.2 Location and Installation Clearance ................................................................................................... 122.4.3 ACDS-B and AUDS-B Dimensional Data ......................................................................................... 13-21

2.5 Foundation and Mounting Structure2.5.1 ACDS-B Unit Weights and Point Loading - Aluminum Fin Condenser Unit ........................................... 222.5.2 ACDS-B Unit Weights and Point Loading - Copper Fin Condenser Unit ................................................ 222.5.3 AUDS-B Unit Weights and Point Loading - Aluminum Fin Condenser Unit .......................................... 232.5.4 AUDS-B Unit Weights and Point Loading - Copper Fin Condenser Unit ................................................ 23

2.6 Vibration Isolation Requirement2.6.1 ACDS-B Rubber-in-Shear - with Aluminum Fin Condenser .................................................................. 242.6.2 ACDS-B Rubber-in-Shear - with Copper Fin Condenser ....................................................................... 242.6.3 ACDS-B Spring Isolators - with Aluminum Fin Condenser ................................................................... 252.6.4 ACDS-B Spring Isolators - with Copper Fin Condenser ........................................................................ 252.6.5 AUDS-B Rubber-in-Shear - with Aluminum Fin Condenser ................................................................. 262.6.6 AUDS-B Rubber-in-Shear - with Copper Fin Condenser ...................................................................... 262.6.7 AUDS-B Spring Isolators - with Aluminum Fin Condenser ................................................................... 272.6.8 AUDS-B Spring Isolators - with Copper Fin Condenser ........................................................................ 27

2.7 Piping Connections: ACDS-B / AUDS-B ...................................................................................... 28

2.7.1 ACDS-B Chilled Water Piping ........................................................................................................ 28-292.7A Typical Chilled Water Piping - Three Way Bypass ............................................................... 302.7B Typical Chilled Water Piping - Two Way Bypass ................................................................. 30

2.7.2 Multiple Chiller Water Piping ............................................................................................................. 282.7.2.1 Parallel Multiple Chiller Water Piping ................................................................................ 282.7C Typical Parallel Chiller Chilled Water Piping ....................................................................... 282.7.2.2 Series Multiple Chiller Water Piping .................................................................................. 282.7D Typical Series Chiller Chilled Water Piping ......................................................................... 28

2.7.3 ACDS-B Chilled Water Quality ............................................................................................................ 282.7.4 AUDS-B Condensing Unit Connections .............................................................................................. 29

2.7.4.1 General Condensing Unit Connections Applications ......................................................... 292.7E Condensing Unit Typical Hot Gas Bypass Piping ................................................................ 30

2.8 Electrical Connections: ACDS-B / AUDS-B .................................................................................. 31

2.8.1 Electrical Data Table - Unit ............................................................................................................ 32-332.8.2 Electrical Data Table - Field ........................................................................................................... 34-352.8.3 General Electrical Notes ..................................................................................................................... 36

2.9 Refrigerant Charging Procedure................................................................................................. 37

2.9.1 General Refrigerant Charging Procedures .......................................................................................... 372.9A Refrigerant Line Capacities ............................................................................................................... 372.9.2 AUDS-B Refrigerant Charge Calculation ............................................................................................. 372.9.3 AUDS-B Refrigerant Charging Procedure ........................................................................................... 37

3


Page

3.0 Operation3.1 Qualified Unit Start-up Report (Required for Warranty) ........................................................... 38

3.2 Typical Refrigerant Piping .......................................................................................................... 38

3.2A Typical ACDS-B 015S - 030S Packaged Chiller Refrig. Piping ................................................................ 393.2B Typical ACDS-B 025D - 060D Packaged Chiller Refrig. Piping ............................................................... 393.2C Typical AUDS-B 015S - 030S Condensing Unit Refrig. Piping ................................................................ 403.2D Typical AUDS-B 025D - 060D Condensing Unit Refrig. Piping .............................................................. 40

3.3 Pre-start-up Procedure for ACDS-B and AUDS-B Systems ............................................................ 41

3.4 Start-up and Reporting for ACDS-B and AUDS-B Systems ........................................................... 41

3.5 Lubrication - ACDS-B / AUDS-B ................................................................................................... 42

3.5.1 General ............................................................................................................................................. 423.5.2 Oil Level ............................................................................................................................................ 423.5.3 Oil Type ............................................................................................................................................. 42

3.6 Chilled Fluid Flow Rate ACDS-B or Split-System Chillers ........................................................... 42

3.6A Unit Cooler Reference Table - DX Coolers ............................................................................................ 423.6B Water Side Pressure Drop Curves - DX Coolers ..................................................................................... 43

3.7 System Control ACDS-B and AUDS-B .......................................................................................... 44

3.7.1 Capacity Control System .................................................................................................................... 443.7.2 Capacity Control Staging for Single Circuit Units ................................................................................. 453.7.3 Capacity Control Staging for Dual Circuit Units ................................................................................... 453.7.4 Condenser Fan Cycling ....................................................................................................................... 46

3.8 Electrical Controls Description .............................................................................................. 47-48

3.9 DB Director - Microcomputer System Control ............................................................................ 483.9.1 Precautions .......................................................................................................................... 483.9.2 Computer Operation ...................................................................................................... 48-49

3.9.2.1 Keypad Display Quick Reference - Display Status ............................................................. 50

3.9.2.2 Keypad Display Quick Reference - Entry Keys ................................................................... 513.9.2.3 Display Data ................................................................................................................... 523.9.2.4 Read and Enter Data ........................................................................................................ 533.9.2.5 Capacity Control States ................................................................................................... 543.9.2.6 Circuit Control States ...................................................................................................... 553.9.2.7 Alarms Section .......................................................................................................... 56-573.9.2.8 Control States Quick Reference - Chiller Applications ....................................................... 58

3.9.3 Control Functions and Operations ....................................................................................... 59

3.9.3.1 Compressor and Unloader Staging .................................................................................. 59

3.9.3.2 Condenser Fan Control .................................................................................................... 603.9.3.3 Pumpdown Control ........................................................................................................ 603.9.3.4 Anti-Recycle ................................................................................................................... 603.9.3.5 Lead / Lag (optional feature) ........................................................................................... 603.9.3.6 Chilled Water / Air Reset .................................................................................................. 603.9.3.7 Customer Control Interlock ............................................................................................. 603.9.3.8 Low Pressure Unload ...................................................................................................... 613.9.3.9 High Pressure Unload ...................................................................................................... 613.9.3.10 High Amp Unload (optional Load Limiting) ..................................................................... 613.9.3.11 Low Ambient Temperature Limit (optional) ..................................................................... 613.9.3.12 Power-up Delay .............................................................................................................. 613.9.3.13 Electronic Expansion Valve Control (optional) .................................................................. 61

3.9.4 General Servicing Procedure .......................................................................................... 61

3.9.5ATypical Power Wiring (Two Compressor Model) ............................................................. 623.9.5B Typical Control Wiring (Two Compressor Model) ...................................................... 63-64

4


3.10 DB Director - Circuit Operationfor ACDS-B or AUDS-B Split-System Chiller ............................................................ 65or AUDS-B Leaving Air Control with DX Coil ......................................................... 65

3.10.1 Unit on Standby ................................................................................................................. 653.10.2 Unit Run Cycle Sequence - (Increasing Load) ...................................................................... 65

3.10.2.1 Step 1 Increasing Load .......................................................................................... 653.10.2.2 Step 2 Increasing Load .......................................................................................... 653.10.2.3 Step 3 Increasing Load .......................................................................................... 653.10.2.4 Step 4 Increasing Load ......................................................................................... 65

3.10.3 Unit Run Cycle Sequence - (Decreasing Load) ..................................................................... 663.10.3.1 Step 4 Decreasing Load ........................................................................................ 663.10.3.2 Step 3 Decreasing Load ........................................................................................ 663.10.3.3 Step 2 Decreasing Load ........................................................................................ 66

3.10.3.1 Step 1 Decreasing Load ........................................................................................ 66

3.11 DB Director - Circuit Operation for AUDS-B Return Air Controlof Constant Volume with DX Coil 843.11.1 Unit on Standby ................................................................................................................. 673.11.2 Unit Run Cycle Sequence - (Increasing Load) ...................................................................... 67

3.11.2.1 Step 1 Increasing Load ......................................................................................... 673.11.2.2 Step 2 Increasing Load ......................................................................................... 673.11.2.3 Step 3 Increasing Load ......................................................................................... 673.11.2.4 Step 4 Increasing Load ......................................................................................... 67

3.11.3 Unit Run Cycle Sequence - (Decreasing Load) ..................................................................... 683.11.3.1 Step 4 Decreasing Load ........................................................................................ 683.11.3.2 Step 3 Decreasing Load ........................................................................................ 683.11.3.3 Step 2 Decreasing Load ........................................................................................ 683.11.3.4 Step 1 Decreasing Load ........................................................................................ 68

3.12 DB Director - Circuit Operationfor AUDS-B Suction Pressure Control for multiple evaporators ................................................. 693.12.1 Unit on Standby ................................................................................................................. 693.12.2 Unit Run Cycle Sequence - (Increasing Load) ...................................................................... 69

3.12.2.1 Step 1 Increasing Load .......................................................................................... 69

3.12.2.2 Step 2 Increasing Load .......................................................................................... 693.12.2.3 Step 3 Increasing Load .......................................................................................... 69

3.12.2.4 Step 4 Increasing Load .......................................................................................... 69

3.12.3 Unit Run Cycle Sequence - (Decreasing Load) ..................................................................... 703.12.3.1 Step 4 Decreasing Load ......................................................................................... 70

3.12.3.2 Step 3 Decreasing Load ......................................................................................... 703.12.3.3 Step 2 Decreasing Load ......................................................................................... 70

3.12.3.4 Step 1 Decreasing Load ......................................................................................... 70

4.0 Maintenance4.1 General Maintenance................................................................................................................. 714.2 Periodic Inspection .................................................................................................................... 714.3 Monthly Inspection ................................................................................................................... 714.4 Vessel Maintenance ................................................................................................................... 71

4.4.1 General Unit Efficiency and Performance ........................................................................... 714.4.2 Cooler Cleaning.................................................................................................................. 71

4.5 Air Cooled Condenser Cleaning ................................................................................................. 714.6 Electrical Malfunction ............................................................................................................... 714.7 Compressor Maintenance ......................................................................................................... 724.8 Refrigerant Charge ................................................................................................................... 724.9 Troubleshooting ........................................................................................................................ 73

4.9.1 Unit will not start ............................................................................................................... 734.9.2 Compressor hums but does not start ................................................................................. 734.9.3 Compressor cycles on low pressure control ........................................................................ 73

4.9.4 Compressor cycles on high pressure control ................................................................................... 734.10 Start-Up and Maintenance Log Sheet .................................................................................... 74-75

4.11 Temperature and Pressure Table ................................................................................................. 76

Page

5

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○1.0 GENERAL INFORMATION

1.1 Introduction

This manual is designed to provide all necessaryinformation for installation, operation andmaintenance of the latest generation of Dunham-Bushscroll compressor package units. These packagesinclude air cooled water chiller machines, and air cooledcondensing units.

To use this manual effectively, you must first determineyour unit model number from the unit nameplate.Since this manual is comprehensive for a wide varietyof units, you should be careful to use only thosesections which apply to your model. Note that eachsection is clearly marked as to the applicable models.

The AUDS-B is a condensing unit without a mountedevaporator. It is designed for remote DX water chilleror air cooling coil applications. Due to the evaporatorbeing remotely mounted, the AUDS-B machine is givena factory electrical test only.

1.2 Product Identification

To assure satisfactory operation and to avoid damageto the unit, the installation should be made by aqualified refrigeration mechanic. It is assumed thatthe reader of his manual and those who install, operateand maintain this equipment have a basicunderstanding of the principles of air conditioning,refrigeration and electrical controls. These instructionsare general in nature and are for standard catalog units.Non-standard units may vary in some respects fromthese instructions.

Your Dunham-Bush package has been manufacturedunder a careful quality control system and has beenfactory run tested as a final verification of reliability. Ifit is installed, operated and maintained with care andattention to these instructions, it will give many yearsof satisfactory service.

Air Cooled Packaged Chiller Models and Condensing Units for Use withDX Coil Banks or Remote Coolers for Split-System Chillers

MODEL UNIT SIZE DESCRIPTION015S,020S,025S,027S,030S 1 Tandem Scroll Compressor - 1 Refrigerant Circuit

ACDS-B / AUDS-B 025D,030D,035D,040D,045D 2 Tandem Scroll Compressors - 2 Refrigerant Circuits050D,055D,057D,060D,065D

070D,080D,090D,100D

A C D S B 060 D AR Z B

Microcomputer Control

Air Cooled CondenserR22 Base Refrigerant

Packaged Chiller (C)

Condensing Unit (U) CD 208/3/60 Main PowerAN 230/3/60 Main Power

AR 460/3/60 Main Power

AS 575/3/60 Main Power

Unit Vintage

Nominal Capacity in Tons

Direct Expansion Evaporator

Tandem Scroll Compressor

Refrigerant Circuits

(S) Single - 015S, 020S, 025S, 027S, 030S(D) Dual - 025D, 030D, 035D, 040D, 045D

050D, 055D, 057D, 060D, 065D,

070D, 080D, 090D, 100D

6

ACDS-B & AUDS-B 021S, 024S, 027S, 030S, 035S

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○1.0 GENERAL INFORMATION (CONT.)

1.3 Physical Specifications: English I.P. & S.I. Units

UNIT MODEL 015S 020S 025S 027S 030S

Quantity of Compressors / Circuit 2 / 1 2 / 1 2 / 1 2 / 1 2 / 1

STANDARD COOLER for ACDS-B or

Remote Mounted Cooler (RCH1 Option) CHS006601B CHS006601B CHS007601B CHS007601B CHS008601A

for AUDS-B Split-System Chiller

Water Volume, Gallons (Liters) 3.4 (12.9) 3.4 (12.9) 5.5 (20.8) 5.5 (20.8) 7.0 (26.5)

Minimum Flow Rate, GPM (L/S) 29 (1.83) 29 (1.83) 50 (3.15) 50 (3.15) 56 (3.53)

Maximum Flow Rate, GPM (L/S) 97 (6.12) 97 (6.12) 168 (10.60) 168 (10.60) 172 (10.85)

Water Conn. Size In/Out (Type) 3"NPTE 3"NPTE 3"NPTE 3"NPTE 3"NPTE

OPTIONAL COOLER for 42°F (5.5°C) LWT

CH2 Option(1) for ACDS-B or NR NR NR NR NR

Remote Mounted Cooler (RCH2) Option


Water Volume, Gallons (Liters) NR NR NR NR NR

Minimum Flow Rate, GPM (L/S) NR NR NR NR NR

Maximum Flow Rate, GPM (L/S) NR NR NR NR NR

Water Conn. Size In/Out (Type) NR NR NR NR NR


CH3 Option(2) for ACDS-B or NR CHS007601A CHS007601A CHS008601A NR



Water Volume, Gallons (Liters) NR 27 (102.2) 27 (102.2) 35 (132.5) NR

Minimum Flow Rate, GPM (L/S) NR 37 (2.33) 37 (2.33) 56 (3.53) NR

Maximum Flow Rate, GPM (L/S) NR 101 (6.37) 101 (6.37) 168 (10.60) NR

Water Conn. Size In/Out (Type) NR 3"NPTE 3"NPTE 3"NPTE NR

CONDENSER L216 L216 L216 L216 L216

Fan Quantity - All 30" (766mm) Diameter 2 2 2 2 2

Motor Quantity(3) (1) 2 (1) 2 (1) 2 (1) 2 (1) 2

Standard Fans - Nominal RPM 1140 1140 1140 1140 1140

Standard Fans - HP (4) (1.0) 1.5 (1.0) 1.5 (1.0) 1.5 (1.0) 1.5 (1.0) 1.5

Standard Fans - (kW) (4) (.76) 1.15 (.76) 1.15 (.76) 1.15 (.76) 1.15 (.76) 1.15

Opt. Extra Quiet Fans - Nominal RPM 855 855 855 855 855

Opt. Extra Quiet Fan Motor - HP (kW) (4) 1.0 (0.76) 1.0 (0.76) 1.0 (0.76) 1.0 (0.76) 1.0 (0.76)

GENERAL DATA

Min.Starting/Operating Ambient°F (°C) (4) 30 (-1.1) 30 (-1.1) 30 (-1.1) 30 (-1.1) 30 (-1.1)

with HGBP, °F (°C) (4) 40 (4.4) 40 (4.4) 40 (4.4) 40 (4.4) 40 (4.4)

Low Ambient Option, °F (°C) (5) 0 (-18) 0 (-18) 0 (-18) 0 (-18) 0 (-18)

Extra Low Ambient Option, °F (°C) (6) -20 (-29) -20 (-29) -20 (-29) -20 (-29) -20 (-29)

Number of Circuits 1 1 1 1 1

Approximate Refrig. Chg. lbs. (kgs) R22 33 (15.0) 45 (20.4) 57 (25.9) 62 (28.1) 70 (31.8)

Approximate Refrig. Chg. lbs. (kgs) R407C 33 (15.0) 45 (20.4) 57 (25.9) 62 (28.1) 70 (31.8)

ACDS-B Weights

Shipping Wt., lbs. (kgs) Alum. Fin Cond. 1636 (743) 1674 (760) 1722 (782) 1807 (820) 1957 (888)

Shipping Wt., lbs. (kgs) Copper Fin Cond. 1865 (847) 1903 (864) 1952 (886) 2037 (925) 2304 (1046)

Operating Wt., lbs.(kgs) Alum. Fin Cond. 1668 (757) 1720 (781) 1768 (803) 1866 (847) 2016 (915)

Operating Wt., lbs.(kgs) Copper Fin Cond. 1897 (861) 1949 (885) 1998 (907) 2096 (952) 2363 (1072)

AUDS-B Weights


Shipping Wt., lbs. (kgs) Copper Fin Cond. 1628 (739) 1616 (734) 1651 (750 1669 (758) 1927 (875)



NOTES: (1) CH2 or RCH2 - Oversized cooler required where indicated for 42°F (5.5°C) LWT. NR - Not Required(2) CH3 or RCH3 - Oversized cooler required where indicated for 40°F (4.5°C) LWT. NPTE - National Pipe Thread External(3) Units with Low Ambient Option use (1) 1.0 HP (0.76 kW) in lieu of (1) 1.5 HP (1.15kW) fan motor per circuit(4) Minimum Starting/Operation Ambient with a maximum of 5 MPH wind across coil & minimum 25% load(5) Low Ambient Option requires (1) 1 HP (0.76 kW) variable speed fan, motor per circuit(6) Extra Low Ambient Option requires electronic expansion valve(s), variable speed fan, 50% glycol, 50%

minimum load and maximum 5 MPH wind across coil

7

ACDS-B & AUDS-B 025D, 030D, 035D, 040D, 045D

1.0 GENERAL INFORMATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○


UNIT MODEL 025D 030D 035D 040D 045D

Quantity of Compressors / Circuit 4 / 2 4 / 2 4 / 2 4 / 2 4 / 2


Remote Mounted Cooler (RCH1 Option) CHD007601B CHD007601B CHD008601B CHD008601B CHD010601B


Water Volume, Gallons (Liters) 5.5 (20.8) 5.5 (20.8) 7 (26.5) 7 (26.5) 10.7 (40.5)



Water Conn. Size In/Out (Type) 3" NPTE 3" NPTE 4" NPTE 4" NPTE 4" NPTE


CH2 Option(1) for ACDS-B or CHD008601A CHD008601A CHD010601B CHD010601B NR



Water Volume, Gallons (Liters) 7.7 (29.1) 7.7 (29.1) 10.7 (40.5) 10.7 (40.5) NR

Minimum Flow Rate, GPM (L/S) 56 (3.53) 56 (3.53) 78 (4.92) 78 (4.92) NR

Maximum Flow Rate, GPM (L/S) 168 (10.60) 168 (10.60) 315 (19.87) 315 (19.87) NR

Water Conn. Size In/Out (Type) 3" NPTE 3" NPTE 4" NPTE 4" NPTE NR


CH3 Option(2) for ACDS-B or CHD008601A CHD010601A CHD011601A CHD011601B CHD011601A



Water Volume, Gallons (Liters) 7.7 (29.1) 10.7 (40.5) 12.9 (48.8) 12.9 (48.8) 12.9 (48.8)



Water Conn. Size In/Out (Type) 3" NPTE 4" NPTE 4" NPTE 4" NPTE 4" NPTE



Motor Quantity(3) (2) 4 (2) 4 (2) 4 (2) 4 (2) 4


Standard Fans - HP (4) 1.0 1.0 1.0 (1.0) 1.5 (1.0) 1.5

Standard Fans - (kW) (4) (.76) 1.15 (.76) 1.15 (.76) 1.15 (.76) 1.15 (.76) 1.15



GENERAL DATA


with HGBP, °F (°C) (4) 40 (4.4) 40 (4.4) 40 (4.4) 40 (4.4) 40 (4.4)




Approximate Refrig. Chg, lbs. (kgs) R22 62 (28.1) 75 (34.0) 83 (37.6) 93 (42.2) 109 (49.4)

Approximate Refrig. Chg, lbs. (kgs) R407C 62 (28.1) 75 (34.0) 83 (37.6) 93 (42.2) 109 (49.4)

ACDS-B Weights





AUDS-B Weights



Operating Wt., lbs.(kgs) Alum. Fin Cond. 3123 (1418) 3123 (1418 ) 3123 (1418) 3148 (1429) 3220 (1462)




8

ACDS-B & AUDS-B 050D, 055D, 057D, 060D

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○1.0 GENERAL INFORMATION (CONT.)


UNIT MODEL 050D 055D 057D 060D

Quantity of Compressors / Circuit 4 / 2 4 / 2 4 / 2 4 / 2


Remote Mounted Cooler (RCH1 Option) CHD011601B CHD011601B CHD011601B CHD013601B


Water Volume, Gallons (Liters) 12.9 (49.0) 12.9 (49.0) 12.9 (49.0) 18.1 (68.5)

Minimum Flow Rate, GPM (L/S) 86 (5.44) 86 (5.44) 86 (5.44) 101 (6.39)

Maximum Flow Rate, GPM (L/S) 315 (19.23) 315 (19.23) 315 (19.23) 420 (25.76)

Water Conn. Size In/Out (Type) 4" NPTE 4" NPTE 4" NPTE 4" NPTE


CH2 Option(1) for ACDS-B or NR NR NR NR



Water Volume, Gallons (Liters) NR NR NR NR

Minimum Flow Rate, GPM (L/S) NR NR NR NR

Maximum Flow Rate, GPM (L/S) NR NR NR NR

Water Conn. Size In/Out (Type) NR NR NR NR


CH3 Option(2) for ACDS-B or CHD013601B CHD013601B CHD013601B NR



Water Volume, Gallons (Liters) 18.1 (68.5) 18.1 (68.5) 18.1 (68.5) NR

Minimum Flow Rate, GPM (L/S) 101 (6.39) 101 (6.39) 101 (6.39) NR

Maximum Flow Rate, GPM (L/S) 420 (25.76) 420 (25.76) 420 (25.76) NR

Water Conn. Size In/Out (Type) 4" NPTE 4" NPTE 4" NPTE NR

CONDENSER L216 L312 L216 L216

Fan Quantity - All 30" (766mm) Diameter 4 4 6 6

Motor Quantity(3) (2) 4 (2) 4 (2) 6 (2) 6

Standard Fans - Nominal RPM 1140 1140 1140 1140

Standard Fans - HP (4) (1.0) 1.5 (1.0) 1.5 (1.0) 1.5 (1.0) 1.5

Standard Fans - (kW) (4) (.76) 1.15 (.76) 1.15 (.76) 1.15 (.76) 1.15

Opt. Extra Quiet Fans - Nominal RPM 855 855 855 855

Opt. Extra Quiet Fan Motor - HP (kW) (4) 1.0 (0.76) 1.0 (0.76) 1.0 (0.76) 1.0 (0.76)

GENERAL DATA

Min.Starting/Operating Ambient°F (°C) (4) 30 (-1.1) 30 (-1.1) 30 (-1.1) 30 (-1.1)

with HGBP, °F (°C) (4) 40 (4.4) 40 (4.4) 40 (4.4) 40 (4.4)

Low Ambient Option, °F (°C) (5) 0 (-18) 0 (-18) 0 (-18) 0 (-18)

Extra Low Ambient Option, °F (°C) (6) -20 (-29) -20 (-29) -20 (-29) -20 (-29)

Number of Circuits 2 2 2 2

Approximate Refrig. Chg. lbs. (kgs) R22 119 (54.0) 130 (59.0) 136 (61.7) 140 (63.5)

Approximate Refrig. Chg. lbs. (kgs) R407C 119 (54.0) 130 (59.0) 136 (61.7) 140 (63.5)

ACDS-B Weights

Shipping Wt., lbs. (kgs) Alum. Fin Cond. 3910 (1775) 4228 (1920) 4649 (2111) 4649 (2111)

Shipping Wt., lbs. (kgs) Copper Fin Cond. 4362 (1980) 4926 (2236) 5325 (2418) 5325 (2418)

Operating Wt., lbs.(kgs) Alum. Fin Cond. 4061 (1844) 4379 (1988) 4800 (2179) 4800 (2179)

Operating Wt., lbs.(kgs) Copper Fin Cond. 4513 (2049) 5077 (2305) 5476 (2486) 5476 (2486)

AUDS-B Weights

Shipping Wt., lbs. (kgs) Alum. Fin Cond. 3123 (1418) 3430 (1557) 3845 (1746) 3841 (1744)

Shipping Wt., lbs. (kgs) Copper Fin Cond. 3575 (1623) 4128 (1874) 4520 (2052) 4516 (2050)

Operating Wt., lbs.(kgs) Alum. Fin Cond. 3242 (1472) 3560 (1616) 3981 (1807) 3981 (1807)

Operating Wt., lbs.(kgs) Copper Fin Cond. 3694 (1677) 4258 (1933) 4656 (2114) 4656 (2114)



9

ACDS-B & AUDS-B 065D, 070D, 080D, 090D, 100D

1.0 GENERAL INFORMATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○


UNIT MODEL 065D 070D 080D 090D 100D

Quantity of Compressors / Circuit 4 4 4 4 4


Remote Mounted Cooler (RCH1 Option) CXD1209F09 CXD1209F09 CXD1209F09 CXD1209B07 CXD12120B07


Water Volume, Gallons (Liters) 28 (106) 28 (106) 28 23 (87.1) 30 (1136)

Minimum Flow Rate, GPM (L/S) 112/6.94 112/6.94 112/6.94 140/8.68 188/11.65

Maximum Flow Rate, GPM (L/S) 365/22.63 365/22.63 365/22.63 380/23.56 459/28.45

Water Conn. Size In/Out (Type) 4" VIC 4" VIC 4" VIC 4" VIC 4" VIC



















Motor Quantity(3) (2) 6 (2) 6 (2) 6 (2) 6 (2) 8


Standard Fans - HP (4) (1) 1.5 (1) 1.5 (1) 1.5 (1) 1.5 (1) 1.5

Standard Fans - (kW) (4) (0.76) 1.15 (0.76) 1.15 (0.76) 1.15 (0.76) 1.15 (0.76) 1.15



GENERAL DATA


with HGBP, °F (°C) (4) 49 (4.4) 49 (4.4) 49 (4.4) 49 (4.4) 49 (4.4)




Approximate Refrig. Chg, lbs. (kgs) R22 125 103 150 160 165

Approximate Refrig. Chg, lbs. (kgs) R407C

ACDS-B Weights

Shipping Wt., lbs. (kgs) Alum. Fin Cond.

Shipping Wt., lbs. (kgs) Copper Fin Cond.

Operating Wt., lbs.(kgs) Alum. Fin Cond.

Operating Wt., lbs.(kgs) Copper Fin Cond.

AUDS-B Weights

Shipping Wt., lbs. (kgs) Alum. Fin Cond.

Shipping Wt., lbs. (kgs) Copper Fin Cond.

Operating Wt., lbs.(kgs) Alum. Fin Cond.

Operating Wt., lbs.(kgs) Copper Fin Cond.



10

2.0 INSTALLATION ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

2.1 General ACDS-B/AUDS-BModels ACDS-B packaged chillers are designed to coolwater or other non-corrosive liquids. Water is circulatedthrough the direct expansion cooler where it is cooledto the desired temperature then circulated to coolingcoils for air conditioning, or to other types of heatexchangers for process cooling.

AUDS-B Model condensing units are designed to servea wide variety of field-installed evaporators, withinterconnecting piping to be connected in the field.When connected to a direct expansion cooler, the modelAUDS-B condensing unit operates the same as an ACDS-B packaged chiller. When connected to one or moreDX coil banks, the unit is used to cool and dehumidifyducted air.

Care should be taken to see that the equipment isproperly installed and adjusted. An installer or operatorshould first become familiar with the informationcontained in this manual. Installation of models AUDS-B requiring field-installed refrigeration piping shouldonly be made by a qualified refrigeration technician.

2.2 Inspection ACDS-B/AUDS-BWhen the equipment is delivered, it is important thatthe following inspection be completed in the presenceof the carrier’s representative:

1. Check all crates and cartons received against the Billof Lading/Shipping Papers to be sure they agree.

2. Check the model number and the electricalcharacteristics on the nameplate to determine if theyare correct.

3. Check for freight damage, shortages or otherdiscrepancies and note them on the delivery receiptbefore signing.

In the event that any damage is found, a damage claimshould immediately be filed by the purchaser againstthe delivering carrier as all shipments are made at thepurchaser’s risk.

2.3 Handling Storage & Rigging

2.3.1 General ACDS-B/AUDS-B HandlingInstructions

Each unit has been carefully tested at the factory whereevery precaution is taken to assure that the unit reachesyou in perfect condition. It is very important that theriggers and movers should use the same care andprecaution in moving the equipment into place. Makesure that chains, cables, or other moving equipmentare placed so as to avoid damage to the unit or piping.The refrigerant piping must not be used as a ladder oras a hand hold. Do not attach a chain hoist sling to thepiping or equipment. Move the unit in an uprightposition and let it down gently from trucks or rollers.

2.3.2 StorageThis equipment is designed for outdoor use but mustbe protected from physical damage if stored beforeinstallation.

2.3.3 ACDS-B/AUDS-B Rigging andMoving

This equipment is too large to be carried by a forkliftwithout serious damage so rigging is required.

Figure 2.3.3.1

11

2.0 INSTALLATION ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

2.4 Space and ClearanceRequirementsACDS-B/AUDS-B

2.4.1 General Space and ClearanceRequirements

The dimensional data and space requirements are givenon pages 13 thru 21. Refer to 2.4.2 for location andinstallation clearances and 2.4.3 for dimensionalrequirements. The most important consideration whichmust be taken into account when deciding upon thelocation of air cooled equipment, is the provision for asupply of ambient air to the condenser, and removal ofheated air from the condenser area. Where this essentialrequirement is not provided, it will result in highercondensing temperatures, which cause poor operation,higher power consumption and possibly, eventualfailure of equipment. Units must not be located in thevicinity of steam, hot air or fume exhausts.

Another consideration which must be taken is that theunit should be mounted away from noise sensitivespaces and must have adequate support to avoidvibration and noise transmission into the building. Unitsshould be mounted over corridors, utility areas, restrooms or other auxiliary areas where sound levels arenot as important a factor. Sound and structuralconsultants should be retained for recommendationson critical installations.

12

2.4.2 Location and Installation Clearance - ACDS-B & AUDS-B 015S-100D

2.0 INSTALLATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

13


2.4.3 Dimensional Data: ACDS-B 015S to 030S

022508ABCAT

14


2.4.3 Dimensional Data: ACDS-B & AUDS-B 025D to 055D

022509ABCAT

15


2.4.3 Dimensional Data: ACDS-B 057D and 060D

022510ABCAT1

16


2.4.3 Dimensional Data: ACDS-B 065D and 100D

024613AACAT

17


2.4.3 Dimensional Data: AUDS-B 015S to 030S

022555ABCAT

18


2.4.3 Dimensional Data: AUDS-B 025D to 055D

022556ABCAT

19



024302AACAT

20

2.4.3 Dimensional Data: AUDS-B 100D

2.0 INSTALLATION (CONT.)

024303ABCAT

21



022557ABCAT

22

2.5.2 ACDS-B Unit Weights and Point LoadingCopper Fin Condenser Unit


2.5 Foundation or Mounting Structure

Foundations must be level within 1/16" per foot, for properoperation and functioning of controls. Provision must bemade for supporting the individual load points as shown inthe unit dimensions on 2.4.3 and unit weight and point

loading charts 2.5.1 - 2.5.4. Roof mounted units must besupported on adequate steel structures. If units are locatedon the ground level, a concrete base is recommended.

2.5.1 ACDS-B Unit Weights and Point LoadingAluminum Fin Condenser Unit

Drawing No. 024397AACAT


UNIT # POS (WEIGHT IN LBS) TOTAL POS (WEIGHT IN KGS) TOTAL DIMENSIONS

MODEL FANS #1 #2 #3 #4 #5 #6 LBS #1 #2 #3 #4 #5 #6 KGS A B C D

015S 2 532 646 405 417 -- -- 1897 242 293 184 189 -- -- 861 20.00 57.00 -- 40.00

020S 2 588 719 459 486 -- -- 1949 267 326 208 221 -- -- 885 20.00 57.00 -- 40.00

025S 2 636 771 494 509 -- -- 1997 289 350 224 231 -- -- 907 20.00 57.00 -- 40.00

027S 2 415 524 557 591 -- -- 2096 188 238 253 268 -- -- 952 20.00 57.00 -- 40.00

030S 2 424 544 565 609 -- -- 2363 192 247 257 276 -- -- 1073 20.00 57.00 -- 40.00

025D 4 1049 1161 914 1026 -- -- 3941 476 527 415 466 -- -- 1789 20.00 57.00 -- 83.00

030D 4 1093 1176 958 1041 -- -- 4058 496 534 435 473 -- -- 1842 20.00 57.00 -- 83.00

035D 4 1093 1176 958 1041 -- -- 4165 496 534 435 473 -- -- 1891 20.00 57.00 -- 83.00

040D 4 1189 1209 1053 1074 -- -- 4190 540 549 478 488 -- -- 1902 20.00 57.00 -- 83.00

045D 4 1199 1240 1064 1105 -- -- 4262 544 563 483 502 -- -- 1935 20.00 57.00 -- 83.00

050D 4 1208 1269 1073 1134 -- -- 4512 548 576 487 515 -- -- 2048 20.00 57.00 -- 83.00

055D 4 1208 1269 1073 1134 -- -- 5076 548 576 487 515 -- -- 2305 20.00 57.00 -- 83.00

057D 6 1107 1077 1541 1408 868 766 5476 503 489 700 639 394 348 2486 20.00 43.00 46.00 83.00

060D 6 1116 1106 1556 1451 871 775 5476 507 502 706 659 395 352 2486 20.00 43.00 46.00 83.00

065D 6 1274 1126 1559 1201 1101 1072 7333 579 512 708 545 500 487 3331 20.00 43.00 49.00 83.00

070D 6 1291 1189 1578 1273 1101 1072 7504 586 540 717 578 500 487 3408 20.00 43.00 49.00 83.00

080D 6 1336 1235 1631 1369 1171 1204 7946 607 561 741 622 532 547 3610 20.00 43.00 49.00 83.00

090D 6 1354 1301 1651 1445 1171 1204 8126 615 591 750 656 532 547 3691 20.00 43.00 49.00 83.00

100D 8 1408 1303 2021 2001 1346 1043 9122 639 592 918 909 611 473 4142 20.00 59.50 68.50 83.00

FIELD: INSTALL ISOLATORS AT THE CORRESPONDING LOAD POINTS.


TOP VIEW

TOP VIEW

CNTBOXEND

CNTBOXEND



015S 2 446 558 324 340 -- -- 1668 202 253 147 154 -- -- 757 20.00 57.00 -- 40.00

020S 2 465 565 343 347 -- -- 1720 211 257 156 158 -- -- 781 20.00 57.00 -- 40.00

025S 2 476 591 346 355 -- -- 1768 216 268 157 161 -- -- 803 20.00 57.00 -- 40.00

027S 2 509 613 376 368 -- -- 1866 231 278 171 167 -- -- 847 20.00 57.00 -- 40.00

030S 2 543 661 405 407 -- -- 2016 247 300 184 185 -- -- 915 20.00 57.00 -- 40.00

025D 4 864 1006 738 880 -- -- 3488 392 457 335 400 -- -- 1584 20.00 57.00 -- 83.00

030D 4 908 1021 782 895 -- -- 3606 412 464 355 406 -- -- 1637 20.00 57.00 -- 83.00

035D 4 948 1034 822 908 -- -- 3712 430 469 373 412 -- -- 1685 20.00 57.00 -- 83.00

040D 4 951 1044 825 917 -- -- 3737 432 474 375 416 -- -- 1697 20.00 57.00 -- 83.00

045D 4 960 1071 834 945 -- -- 3810 436 486 379 429 -- -- 1730 20.00 57.00 -- 83.00

050D 4 1049 1108 923 981 -- -- 4061 476 503 419 445 -- -- 1844 20.00 57.00 -- 83.00

055D 4 1123 1198 991 1067 -- -- 4379 510 544 450 484 -- -- 1988 20.00 57.00 -- 83.00

057D 6 771 877 928 1052 586 586 4800 350 398 421 478 266 266 2179 20.00 43.00 46.00 83.00

060D 6 771 877 928 1052 586 586 4800 350 398 421 478 266 266 2179 20.00 43.00 46.00 83.00

065D 6 1160 1012 1465 1107 981 952 6678 527 460 666 503 445 432 3033 20.00 43.00 49.00 83.00

070D 6 1177 1075 1484 1179 981 952 6849 534 488 674 536 445 432 3109 20.00 43.00 49.00 83.00

080D 6 1226 1125 1540 1279 1055 1088 7314 557 511 700 581 479 494 3322 20.00 43.00 49.00 83.00

090D 6 1244 1191 1560 1355 1055 1088 7494 565 541 709 615 479 494 3403 20.00 43.00 49.00 83.00

100D 8 1299 1194 1817 1797 1222 919 8248 590 542 825 816 555 417 3745 20.00 59.50 68.50 83.00

23



2.5.3 AUDS-B Unit Weights and Point LoadingAluminum Fin Condenser Unit

2.5.4 AUDS-B Unit Weights and Point LoadingCopper Fin Condenser Unit


FIELD: INSTALL ISOLATORS AT THE

CORRESPONDING LOAD POINTS.


CNTBOXEND

UNIT TOP VIEW

CNTBOXEND

UNIT TOP VIEW


MODEL FANS #1 #2 #3 #4 #5 #6 LBS #1 #2 #3 #4 #5 #6 KGS A B C D015S 2 359 526 238 308 -- -- 1431 163 239 108 140 -- -- 650 20.00 57.00 -- 40.00

020S 2 359 526 238 308 -- -- 1431 163 239 108 140 -- -- 650 20.00 57.00 -- 40.00

025S 2 371 552 241 315 -- -- 1479 168 251 109 143 -- -- 671 20.00 57.00 -- 40.00

027S 2 376 563 243 319 -- -- 1501 171 256 110 145 -- -- 681 20.00 57.00 -- 40.00

030S 2 410 611 272 357 -- -- 1650 186 277 123 162 -- -- 749 20.00 57.00 -- 40.00

025D 4 727 961 601 834 -- -- 3123 330 436 273 379 -- -- 1418 20.00 57.00 -- 83.00

030D 4 727 961 601 834 -- -- 3123 330 436 273 379 -- -- 1418 20.00 57.00 -- 83.00

035D 4 727 961 601 834 -- -- 3123 330 436 273 379 -- -- 1418 20.00 57.00 -- 83.00

040D 4 730 970 604 844 -- -- 3148 331 440 274 383 -- -- 1429 20.00 57.00 -- 83.00

045D 4 739 997 613 871 -- -- 3220 336 453 278 395 -- -- 1462 20.00 57.00 -- 83.00

050D 4 742 1005 616 879 -- -- 3242 337 456 280 399 -- -- 1472 20.00 57.00 -- 83.00

055D 4 816 1096 684 964 -- -- 3560 370 498 311 438 -- -- 1616 20.00 57.00 -- 83.00

057D 6 612 809 629 924 470 537 3981 278 367 286 419 213 244 1807 20.00 43.00 46.00 83.00

060D 6 612 809 629 924 470 537 3981 278 367 286 419 213 244 1807 20.00 43.00 46.00 83.00

065D 6 771 909 578 900 629 863 4650 350 413 262 409 285 392 2111 20.00 43.00 49.00 83.00

070D 6 787 972 597 972 629 863 4821 357 441 271 442 285 392 2188 20.00 43.00 49.00 83.00

080D 6 837 1022 653 1072 703 1000 5286 380 464 296 487 319 454 2400 20.00 43.00 49.00 83.00

090D 6 854 1088 673 1148 703 1000 5466 388 494 305 521 319 454 2481 20.00 43.00 49.00 83.00

100D 8 786 1067 1001 1600 654 779 5887 357 484 455 727 297 354 2674 20.00 59.50 68.50 83.00



015S 2 411 591 288 371 -- -- 1661 187 268 131 168 -- -- 754 20.00 57.00 -- 40.00

020S 2 411 591 288 371 -- -- 1661 187 268 131 168 -- -- 754 20.00 57.00 -- 40.00

025S 2 422 617 291 378 -- -- 1708 192 280 132 172 -- -- 775 20.00 57.00 -- 40.00

027S 2 427 629 293 382 -- -- 1731 194 286 133 173 -- -- 786 20.00 57.00 -- 40.00

030S 2 487 710 347 453 -- -- 1997 221 322 158 206 -- -- 907 20.00 57.00 -- 40.00

025D 4 845 1078 709 943 -- -- 3575 384 489 322 428 -- -- 1623 20.00 57.00 -- 83.00

030D 4 845 1078 709 943 -- -- 3575 384 489 322 428 -- -- 1623 20.00 57.00 -- 83.00

035D 4 845 1078 709 943 -- -- 3575 384 489 322 428 -- -- 1623 20.00 57.00 -- 83.00

040D 4 848 1087 712 952 -- -- 3599 385 493 323 432 -- -- 1634 20.00 57.00 -- 83.00

045D 4 857 1115 721 979 -- -- 3672 389 506 327 444 -- -- 1667 20.00 57.00 -- 83.00

050D 4 859 1123 724 988 -- -- 3694 390 510 329 449 -- -- 1677 20.00 57.00 -- 83.00

055D 4 997 1277 852 1132 -- -- 4258 453 580 387 514 -- -- 1933 20.00 57.00 -- 83.00

057D 6 700 897 777 1073 571 638 4656 318 407 353 487 259 290 2114 20.00 43.00 46.00 83.00

060D 6 700 897 777 1073 571 638 4656 318 407 353 487 259 290 2114 20.00 43.00 46.00 83.00

065D 6 885 1023 671 994 749 983 5306 402 465 305 451 340 447 2410 20.00 43.00 49.00 83.00

070D 6 901 1086 690 1066 749 983 5477 409 493 313 584 340 447 2486 20.00 43.00 49.00 83.00

080D 6 947 1132 743 1162 819 1116 5919 430 514 337 528 372 507 2688 20.00 43.00 49.00 83.00

090D 6 964 1198 763 1238 819 1116 6099 438 544 346 562 372 507 2769 20.00 43.00 49.00 83.00

100D 8 895 1176 1205 1804 777 903 6761 406 534 547 820 353 410 3070 20.00 59.50 68.50 83.00

24

2.6.2 ACDS-B Rubber-in-Shear Vibration Isolators and LocationsFor Units with Copper Fin Condensers

024398AACAT


2.6 Vibration Isolation ACDS-B/AUDS-B

2.6.1 ACDS-B Rubber-in-Shear Vibration Isolators and LocationsFor Units with Aluminum Fin Condensers

Under certain critical conditions, it may be necessary to installvibration isolators under the base of the Packaged Chiller andthe Air Cooled Condenser.

Rubber-in-shear or spring vibration isolators are offered asoptional items. See 2.6.1 or 2.6.2 on pages 24 (ACDS-B / AUDS-B)for mounting location. When spring isolators are used, flexibleconnectors must be installed in the water piping system and inthe refrigerant lines of split systems. Note: These flexibleconnectors must be suitable for the fluid and pressures involves.

When using flexible connectors in refrigerant piping, they mustbe mounted in the refrigerant discharge and liquid lines close

024398AACAT

to the packaged chiller, in a horizontal position and parallel to thecompressor crankshaft.

All piping which is external to the packaged chiller must besupported by spring mounted hangers and any piping whichgoes through the wall, ceiling or floor should be properlysheathed to prevent transmission of piping vibration to thestructure.

When spring isolators are used, electrical service to the unitmust also be flexibly connected, by means of a 36" section offlexible conduit.

25


2.6.3 ACDS-B Spring Vibration Isolators and LocationsFor Units with Aluminum Fin Condensers


2.6.4 ACDS-B Spring Vibration Isolators and LocationsFor Units with Copper Fin Condensers


26


2.6.5 AUDS-B Rubber-in-Shear Vibration Isolators and LocationsFor Units with Aluminum Fin Condensers


2.6.6 AUDS-B Rubber-in-Shear Vibration Isolators and LocationsFor Units with Copper Fin Condensers


27


2.6.7 AUDS-B Spring Vibration Isolators and LocationsFor Units with Aluminum Fin Condensers

024404AACAT

2.6.8 AUDS-B Spring Vibration Isolators and LocationsFor Units with Copper Fin Condensers


28


2.7.1 ACDS-B Chilled Water PipingAfter the unit has been leveled, the external water pipingmay be made up. Be sure water piping is connected tothe correct fittings. The water out connection is closestto the expansion valve (Refrigerant-in) end. A chilledwater flow switch must be installed.

Water flow through the cooler must remain constantfor proper chiller operation. Water pressure gaugesare recommended to check the water pressure and flowrate in the system, before and after the cooler, and todetermine if variations occur in the cooler and system.

The cooler must be freeze protected with the correctpercentage of glycol if ambient temperatures areexpected to be below 32°F. If sub-freezing ambienttemperatures are possible, all exposed field water pipingshould have heater tape and insulation or a glycolmixture to prevent freezing. Main power is required tokeep the sump heaters and cooler heaters on.

When installing pressure taps to measures the amountof pressure drop across the water side of the cooler,the taps should be located in the water piping aminimum of twenty-four (24) inches downstream fromany connections (flange, elbow, etc.).

There are many piping and control systems which maybe used to assure constant water flow through thecooler. A typical system is shown in Figure 2.7A. Ituses a three way motorized valve which operates inresponse to the discharge air temperature of the coolingcoil.

Another system which is sometimes used consists of atwo way modulating control valve, which also respondsto the discharge air temperature of the cooling coil,used in conjunction with a spring loaded bypassregulating valve as shown in Figure 2.7B. The bypassvalve must be set to assure the full flow of circulatingchilled water when the modulating valve is completelyclosed.

Other systems are noted in the ASHRAE Handbook andmay serve equally well. Whatever system is selected,water flow must be constantly maintained through thechiller.

If the system is arranged for the dual purpose of coolingin the summer and heating in the winter, the coolermust be valved off during the heating season so thathot water will not pass through the cooler. This maybe either a manual or automatic change-over operation.There are also times, such as early spring and late fall,

2.7 Piping ConnectionsACDS-B/AUDS-B

when both heating and cooling are required. Thisshould also be considered when designing heating andcooling systems. For various piping arrangementsconsult the ASHRAE Handbook.

2.7.2 Water ConnectionsMultiple Packaged Chillers

Multiple unit packaged chillers have been successfullyapplied to parallel and series piping systems for years.Special attention, however, must be given to theparticulars involved for each application or seriousoperational problems can result.

The following are guidelines which should be followedfor multiple unit application.

NOTE: A constant chilled water flow rate is assumed tobe maintained through all coolers.

2.7.2.1 Parallel Chilled Water Flow UnitsBoth units operate simultaneously, modulating withload variations. Each packaged chiller operatingthermostat senses leaving water temperature usingstandard controls (See Figure 2.7C). The set point ofeach thermostat will be set to maintain the desiredunloading. In addition, for each chiller package, theoptional suction sensing hot gas by-pass valve providesmodulating capacity reduction to approximately 10%on single compressor models with hot gas bypass.

2.7.2.2 Series Chilled Water Flow UnitsUnits should be equally sized. The upstream unit willcarry a larger load because it cools higher temperaturewater. The thermostats sense leaving fluid temperatures(See Figure 2.7D). The Number 1 unit thermostat willunload or cycle off the packaged chiller beforeunloading occurs on the Number 2 unit.

2.7.3 Water Quality ACDS-BCoolers used in these packages are made of steel, copperand brass and are suitable for operation with well-maintained water systems. However, if the water usedin cooler is corrosive, high in mineral content orentrained solids, the water can cause reduced perfor-mance and even failure of heat exchangers. Therefore,it may be necessary to obtain the services of a watertreatment consultant and to provide and maintain watertreatment. This is particularly important with glycolsystems.

See Maintenance Section 4.0 Paragraph 4.4 formaintenance of heat exchangers.

29


2.7.4 Condensing Unit ConnectionsAUDS-B

2.7.4.1 General

The AUDS-B condensing unit may be connected to eithera cooling coil or a remote cooler. When makingconnections, all refrigerant piping should be installedin accordance with local or state codes and the latestissue of ANSI/ASHRAE Standard 15 “Safety Code forMechanical Refrigeration”. Hard drawn type L or Kcopper tubing should be used. Soft tubing, wherebending is required, may be used providing it isprotected in accordance with the local code restrictions.

Careful considerations must always be given to sizingthe liquid line and suction line. For sizing lines, refer toCompressor Piping Manual, Form No. 4120.1 or ASHRAEHandbook.

A suction to liquid heat exchanger must be used if theevaporator is installed more than 30 ft. above thecondensing unit or if the pressure drop in the liquidline exceeds 15 psi. This is necessary to prevent flashinggas at the expansion valve.

When a unit is provided with the hot gas bypass option,a hot gas regulator and solenoid will be mounted atthe condensing unit. The contractor must furnish aninsulated hot gas line with check valve. The line mustbe piped for an evaporator coil or cooler as shown inFigure 2.7E.

For information concerning the installation, operationand servicing of Dunham-Bush coolers, consult the latestrevision of Form 8110.

30

R-OUT R-IN

PUMPM

WAY VALVE

THREE

CHILLER

TANK

EXPANSION

COIL

COOLING

COOLING

COIL

EXPANSION

TANK

CHILLER

TWO

WAY VALVEMPUMP

R-INR-OUT

BYPASS REG.

VALVE


Figure 2.7A

Figure 2.7B

Figure 2.7D

Figure 2.7E

Figure 2.7C

R-OUT R-IN

W-IN

W-OUT

R-OUT R-IN

CHILLER

CHILLER

No. 2

No. 1

TT

T

R-OUT R-IN

FLUID-IN FLUID-OUT

R-OUT R-IN

CHILLER

CHILLER

T

31


All units are wired as completely as possible at the factoryprior to delivery. The connections which must be madeby the installer are to the main power source, controlpower source, separate chiller heater power source andinterlocking the satellite equipment. In connectingpower wiring to the unit, the following precautionsshould be taken:

• All field wiring is to be in accordance with the Na-tional Electrical Code and state and local codes.

• All wiring is to be checked for damage and all termi-nal connections tested for tightness. Unit terminalblocks are to be connected with copper conductorsonly, sized per ampacity listed on unit data plate.

2.8 Electrical ConnectionsACDS-B/AUDS-B

• The power supply should match the unit nameplatein volts, phase and Hertz. Voltage must be within ±10% of nameplate value and voltage imbalance be-tween phases must not exceed 2%.

• For minimum circuit ampacity and maximum fusesize, see Unit Nameplate.

32


2.8.1 Electrical Data (60Hz/3PH)

NOTES: RLA - Rated Load Amps at ARI Conditions of Service *Replace (1) 1.5 HP motor with (1) 1 HP motorMCA - Minimum Circuit Ampacity per circuit on units with Low Ambient OptionMFS / HACR - Maximum fuse or HACR breaker size, protective deviceLRA-XL - Locked Rotor Amps Standard Across the Line Starting

IMPORTANT: See additional notes on pages 36.

Standard UnitElectrical Data

Each CompressorStandard 1140 RPM

CondenserFan Motors

LRA-XL Qty. HPTotal KW

FLAEach

60 HzNom.Volts

ACDS-B Model RLA MCA

MFS/HACR

Qty./Circuit RLA

AK 208 62 68 90 2 23.8 189 2* 1.5 5.9015S AN 230 62 68 90 2 23.8 189 2* 1.5 2.2 5.9

AR 460 33 36 45 2 12.6 94 2* 1.5 3AS 575 24 26 30 2 9.2 74 2* 1.5 2.1AK 208 82 90 110 2 33.6 278 2* 1.5 5.9

020S AN 230 82 90 110 2 33.6 278 2* 1.5 2.9 5.9AR 460 41 45 60 2 16.5 127 2* 1.5 3AS 575 33 36 45 2 13.7 100 2* 1.5 2.1AK 208 97 107 125 2 41.1 350 2* 1.5 5.9

025S AN 230 97 107 125 2 41.1 350 2* 1.5 2.9 5.9AR 460 51 57 70 2 21.8 158 2* 1.5 3AS 575 40 45 60 2 17.4 125 2* 1.5 2.1AK 208 104 116 150 1/1 41.1/48.1 350/425 2* 1.5 5.9

027S AN 230 104 116 150 1/1 41.1/48.1 350/425 2* 1.5 2.9 5.9AR 460 53 59 80 1/1 21.8/23.8 158/187 2* 1.5 3AS 575 44 49 70 1/1 17.4/21.2 125/148 2* 1.5 2.1AK 208 111 123 150 2 48.1 425 2* 1.5 5.9

030S AN 230 111 123 150 2 48.1 425 2* 1.5 2.9 5.9AR 460 55 61 80 2 23.8 187 2* 1.5 3AS 575 48 53 70 2 21.2 148 2* 1.5 2.1

AK 208 127 133 150 4 25.1 189 4* 1.5 5.9025D AN 230 127 133 150 4 25.1 189 4* 1.5 4.4 5.9

AR 460 68 71 80 4 13.6 94 4* 1.5 3AS 575 50 53 60 4 10.1 74 4* 1.5 2.1AK 208 146 154 175 4 29.9 232 4* 1.5 5.9

030D AN 230 146 153 175 4 29.9 232 4* 1.5 4.4 5.9AR 460 75 79 90 4 15.3 125 4* 1.5 3AS 575 57 60 70 4 11.9 100 4* 1.5 2.1AK 208 158 167 200 2/2 31.1/34.8 232/278 4* 1.5 5.9

035D AN 230 158 167 200 2/2 31.2/34.9 232/278 4* 1.5 4.4 5.9AR 460 80 84 100 2/2 16/17.2 125/127 4* 1.5 3AS 575 63 67 80 2/2 12.3/14.5 100/100 4* 1.5 2.1AK 208 168 179 200 3/1 33.6/41.1 278/350 4* 1.5 5.9

040D AN 230 168 178 200 3/1 33.6/41.1 278/350 4* 1.5 5.8 5.9AR 460 85 90 110 3/1 16.5/21.8 127/158 4* 1.5 3AS 575 69 73 90 3/1 13.8/17.5 100/125 4* 1.5 2.1

33

Standard UnitElectrical Data

Each Compressor

LRA-XL Qty. HPTotal KW

FLAEach

60 HzNom.Volts

ACDS-B Model RLA MCA

MFS/HACR

Qty./Circuit RLA

AK 208 191 201 225 4 41.1 350 4* 1.5 5.9045D AN 230 191 201 225 4 41.1 350 4* 1.5 5.8 5.9

AR 460 103 107 125 4 22 158 4* 1.5 3AS 575 80 85 100 4 17.6 125 4* 1.5 2.1AK 208 198 210 250 3/1 41.1/48.1 350/425 4* 1.5 5.9

050D AN 230 198 210 250 3/1 41.1/48.1 350/425 4* 1.5 5.8 5.9AR 460 103 109 125 3/1 21.8/23.8 158/187 4* 1.5 3AS 575 83 88 100 3/1 17.4/21.2 125/148 4* 1.5 2.1AK 208 212 224 250 1/3 41.1/48.1 350/425 4* 1.5 5.9

055D AN 230 212 224 250 1/3 41.1/48.1 350/425 4* 1.5 5.8 5.9AR 460 121 128 150 1/3 25.4/27.3 158/187 4* 1.5 3AS 575 91 96 110 1/3 17.4/21.2 125/148 4* 1.5 2.1AK 208 249 263 300 4 52.8 425 6* 1.5 5.9

057D AN 230 249 262 300 4 52.8 425 6* 1.5 8.7 5.9AR 460 127 132 150 4 26.5 187 6* 1.5 3AS 575 101 106 125 4 21.7 148 6* 1.5 2.1AK 208 249 263 300 4 52.8 425 6* 1.5 5.9

060D AN 230 249 262 300 4 52.8 425 6* 1.5 8.7 5.9AR 460 127 132 150 4 26.5 187 6* 1.5 3AS 575 101 106 125 4 21.7 148 6* 1.5 2.1AK 208 287 305 350 2/2 52.8/71.1 425/480 6* 1.5 5.9

065D AN 230 286 304 350 2/2 52.8/71.1 425/480 6* 1.5 8.7 5.9AR 460 139 147 175 2/2 26.5/33.0 187/225 6* 1.5 3.0AS 575 118 125 150 2/2 24.8/27.2 148/180 6* 1.5 2.1AK 208 323 341 400 4 71.1 480 6* 1.5 8.7 5.9

070D AN 230 323 341 400 4 71.1 480 6* 1.5 5.9AR 460 142 150 175 4 30.7 225 6* 1.5 3.0AS 575 121 128 150 4 26.8 180 6* 1.5 2.1AK 208 352 374 450 2/2 71.1/85.6 480/500 6* 1.5 5.9

080D AN 230 352 373 450 2/2 71.1/85.6 480/500 6* 1.5 8.7 5.9AR 460 162 172 200 2/2 30.7/40.6 225/2500 6* 1.5 3.0AS 575 130 137 150 2/2 26.8/31.1 180/200 6* 1.5 2.1AK 208 361 382 450 4 80.6 500 6* 1.5 5.9AN 230 361 381 450 4 80.6 500 6* 1.5 8.7 5.9

085D AR 460 182 192 225 4 40.6 250 6* 1.5 3.0AS 575 138 146 175 4 31.1 200 6* 1.5 2.1AK 208 361 382 450 4 80.6 500 6* 1.5 5.9

090D AN 230 361 381 450 4 80.6 500 6* 1.5 8.7 5.9AR 460 182 192 225 4 40.6 250 6* 1.5 3.0AS 575 138 146 175 4 31.1 200 6* 1.5 2.1AK 208 373 393 450 4 80.6 500 8* 1.5 5.9

100D AN 230 373 393 450 4 80.6 500 8* 1.5 11.6 5.9AR 460 188 198 225 4 40.6 250 8* 1.5 3.0AS 575 143 150 175 4 31.1 200 8* 1.5 2.1


2.8.1 Electrical Data (60Hz/3PH)

NOTES: RLA - Rated Load Amps at ARI Conditions of Service *Replace (1) 1.5 HP motor with (1) 1 HP single phaseMCA - Minimum Circuit Ampacity motor per circuit on units with Low Ambient OptionMFS / HACR - Maximum fuse or HACR breaker size, protective deviceLRA-XL - Locked Rotor Amps Standard Across the Line Starting

IMPORTANT: See additional notes on page 36.

Standard 1140 RPMCondenserFan Motors

34


2.8.2 Field Wiring — Electrical Data (60Hz/3PH)

NOTE: Single point power is standard for all models ACDSB 015S to ACDSB 100D.

Supply Voltage Single Source Power - Wire Size Range and Quantity

60 Hz. Standard Terminal Block Optional - Unit Mtd. Disconnect Switch

ACDS-B Nom. Qty. Wires Wire Qty. Wires Wire

Model Code Volts Per Pole Size Range Per Pole Size Range

AK 208 1 #12 TO 2/0 1 #14 TO 1/0

015SAN 230 1 #12 TO 2/0 1 #14 TO 1/0AR 460 1 #12 TO 2/0 1 #14 TO 1/0AS 575 1 #12 TO 2/0 1 #14 TO 1/0AK 208 1 #12 TO 2/0 1 #14 TO 1/0




030SAN 230 1 #12 TO 2/0 1 #4 TO 4/0AR 460 1 #12 TO 2/0 1 #14 TO 1/0AS 575 1 #12 TO 2/0 1 #14 TO 1/0

1AK 208 1 #12 TO 2/0 1 #4 TO 4/0

025DAN 230 1 #12 TO 2/0 1 #4 TO 4/0AR 460 1 #12 TO 2/0 1 #14 TO 1/0AS 575 1 #12 TO 2/0 1 #14 TO 1/0AK 208 1 #6 TO 400 MCM 1 #4 TO 350MCM

030DAN 230 1 #6 TO 400 MCM 1 #4 TO 350MCMAR 460 1 #12 TO 2/0 1 #14 TO 1/0AS 575 1 #12 TO 2/0 1 #14 TO 1/0AK 208 1 #6 TO 400 MCM 1 #4 TO 350MCM

035DAN 230 1 #6 TO 400 MCM 1 #4 TO 350MCMAR 460 1 #12 TO 2/0 1 #14 TO 1/0AS 575 1 #12 TO 2/0 1 #14 TO 1/0AK 208 1 #6 TO 400 MCM 1 #4 TO 350MCM

040DAN 230 1 #6 TO 400 MCM 1 #4 TO 350MCMAR 460 1 #12 TO 2/0 1 #14 TO 1/0AS 575 1 #12 TO 2/0 1 #14 TO 1/0

35

NOTE: Single point power is standard for all models ACDSB 015S to ACDSB 100D.

Supply Voltage Single Source Power - Wire Size Range and Quantity

60 Hz. Standard Terminal Block Optional - Unit Mtd. Disconnect Switch

AK 208 1 #6 TO 400 MCM 1 #4 TO 350MCM045D AN 230 1 #6 TO 400 MCM 1 #4 TO 350MCM

AR 460 1 #12 TO 2/0 1 #4 TO 4/0AS 575 1 #12 TO 2/0 1 #14 TO 1/0AK 208 1 #6 TO 400 MCM 1 #4 TO 350MCM

050D AN 230 1 #6 TO 400 MCM 1 #4 TO 350MCMAR 460 1 #12 TO 2/0 1 #4 TO 4/0AS 575 1 #12 TO 2/0 1 #14 TO 1/0AK 208 1 #6 TO 400 MCM 1 #4 TO 350MCM

055D AN 230 1 #6 TO 400 MCM 1 #4 TO 350MCMAR 460 1 #12 TO 2/0 1 #4 TO 4/0AS 575 1 #12 TO 2/0 1 #4 TO 4/0AK 208 1 #6 TO 400 MCM 2 3/0 TO 250MCM

057D AN 230 1 #6 TO 400 MCM 2 3/0 TO 250MCMAR 460 1 #12 TO 2/0 1 #4 TO 4/0AS 575 1 #12 TO 2/0 1 #4 TO 4/0AK 208 1 #6 TO 400 MCM 2 3/0 TO 250MCM

060D AN 230 1 #6 TO 400 MCM 2 3/0 TO 250MCMAR 460 1 #12 TO 2/0 1 #4 TO 4/0AS 575 1 #12 TO 2/0 1 #4 TO 4/0CD 208 1 #6 TO 400 MCM 1 2/0 to 600MCM

065D AN 230 1 #6 TO 400 MCM 1 2/0 to 600MCMAR 460 1 #6 TO 400 MCM 1 #4 TO 350MCMAS 575 1 #12 TO 2/0 1 #4 TO 4/0CD 208 1 #4 TO 500 MCM 1 2/0 to 600MCM



090D AN 230 2 #4 TO 500 MCM 2 2/0 to 600MCMAR 460 1 #6 TO 400 MCM 1 #4 TO 350MCMAS 575 1 #6 TO 400 MCM 1 #4 TO 350MCMCD 208 2 #4 TO 500 MCM 2 2/0 to 600MCM

100D AN 230 2 #4 TO 500 MCM 2 2/0 to 600MCMAR 460 1 #6 TO 400 MCM 1 #4 TO 350MCMAS 575 1 #6 TO 400 MCM 1 #4 TO 350MCM

ACDS-B Model Per Pole Size Range Per Pole Size Range

Nom. Code Volts


2.8.2 Field Wiring — Electrical Data (60Hz/3PH)

Qty. Wires Wire Qty. Wires Wire

36


2.8.1 Electrical Data (60Hz/3PH)General Electrical Notes

1. Main power must be supplied from a single power sourcefield-supplied fused disconnect(s) using dual element timedelay fuses or a HACR rated circuit breaker. Power supply isthree phase unless otherwise shown.

2. The maximum terminal block incoming wire size is shown inthe electrical field wiring data table.

3. Compressor starting is XL only.

4. Control circuit transformer (115VAC) is supplied as standardfeature.

5. Cooler heater power (115VAC) must be field-supplied from aseparate field-mounted fused disconnect (15 amp max. fuse

size).

Nominal Voltage Code Minimum Maximum

208V CD 187V 220V

230V AN 207V 253V

460V AR 414V 506V

575V AS 518V 632V

Supply Voltage:

6. Crankcase heaters are wired in the control circuit. The mainunit power field disconnect and local safety switch must beclosed (on) at all times for heater operation.

7. The compressor crankcase heaters must be energized for 24hours before the unit is initially started or after a prolongedopen disconnect.

8. All field wiring must be in accordance with all applicable localand national codes.

9. Minimum and maximum unit supply voltages are shown in thefollowing tabulated data.

TABLE 30A

Cooler Heater Wattage

Unit Cooler

Model HeaterACDS-B for 44°F (6.7°C) FLA ea. for 42°F (5.5°C) FLA ea. for 40°F (4.5°C) FLA ea. Qty.

Standard CoolerCH2

Optional CoolerCH3

Optional Cooler

015S 280 2.4 280 2.4 280 2.4 1

020S 280 2.4 280 2.4 280 2.4 1

025S 280 2.4 280 2.4 280 2.4 1

027S 280 2.4 280 2.4 280 2.4 1

030S 280 2.4 280 2.4 280 2.4 1

025D 280 2.4 280 2.4 280 2.4 1

030D 280 2.4 280 2.4 420 3.7 1

035D 280 2.4 420 3.7 420 3.7 1

040D 280 2.4 420 3.7 420 3.7 1

045D 420 3.7 420 3.7 420 3.7 1

050D 420 3.7 420 3.7 560 4.9 1

055D 420 3.7 420 3.7 560 4.9 1

057D 420 3.7 420 3.7 560 4.9 1

060D 560 4.9 560 4.9 560 4.9 1

065D 560 4.9 560 4.9 560 4.9 1

070D 560 4.9 560 4.9 560 4.9 1

080D 560 4.9 560 4.9 560 4.9 1

090D 560 4.9 560 4.9 560 4.9 1

100D 420 3.7 420 3.7 420 3.7 2

TABLE 30B

Belt or Strap Type - Crankcase Heater Data

015S 2 140 1.22020S 2 140 1.22025S 2 140 1.22027S 2 140 1.22030S 2 140 1.22025D 4 280 2.44030D 4 280 2.44035D 4 280 2.44040D 4 280 2.44045D 4 280 2.44050D 4 280 2.44055D 4 280 2.44057D 4 280 2.44060D 4 280 2.44065D 4 440 3.82070D 4 600 5.24080D 4 600 5.24090D 4 600 5.24100D 4 600 5.24

Unit Model ASDS-B Qty. Total Watts (70 Watts each) Total FLA (0.61 FLA each)

37


2.9 Refrigerant ChargingProcedure ACDS-B/AUDS-B

2.9.1 General Refrigerant ChargingProcedures

The ACDS-B units are charged at the factory with therefrigerant for which they were designed. The typeand amount of refrigerant are shown on the nameplate.

The AUDS-B units have a gas holding charge of therefrigerant type shown on the nameplate.

Prior to charging an AUDS-B split system and after allpiping has been completed, the system must be pressuretested and the system evacuated. For the proceduresto follow, consult the latest revision of Form 4232.

Table 2.9A Refrigerant Line Capacities

Liquid Discharge Suction

@ 90°F @ 105° F @ 40°F

5/8 OD 12.0 .72 .30

7/8 OD 24.0 1.35 .51

1 1/8 OD 42.0 2.30 .87

1 3/8 OD 59.0 3.50 1.33

1 5/8 OD 74.0 4.96 1.88

2 1/8 OD 146.0 8.61 3.26

2 5/8 OD 225.0 13.70 5.03

Line Size, in.

R-22 Refrigerant Line Charge Lbs./100 Ft.

2.9.2 Charge Calculation: CondensingUnit AUDS-B

Prior to charging your AU condensing unit with fieldinstalled lowside, you must first determine the amountof refrigerant required for your system.

Determine the estimated amount for each circuit and

charge each circuit with this amount. To estimatethe amount of charge for one circuit?

1. Multiply the nominal capacity of the circuit by 2.5 toobtain refrigerant charge in pounds.

2. Determine the length of the liquid line. Refer to Table2.9A which gives the refrigerant charge for differentline sizes per 100 ft. Multiply your length per 100 ft.by the amount shown in the table for your line sizeand saturated temperature conditions.

3. Determine the length of the suction line for onecircuit. Refer to Table 2.9A. Multiply your lengthper 100 ft. by the amount shown in the table foryour line size and saturated temperature conditions.

4. Consult the manufacturer of your low side to obtainthe operating charge.

5. Add the amount from steps 1, 2, 3, 4 to obtain anestimated refrigerant charge per circuit.

2.9.3 Charging AUDS-BOnce the estimated amount of charge required for yoursystem has been determined and the system is leak free,you are ready to begin charging the system.

To charge the unit, attach a drum of refrigerant to thebackseating port of the liquid line valve. Purge thecharging line to remove air, invert the drum and openit to the system. A set of scales should be used toweigh the drum before and after charging to determinethe amount of refrigerant charged into the system.

After the system has been charged and the machine isrunning, the system should once again be checked forleaks to make sure that no leaks have occurred duringthe handling of the equipment.

The unit, if possible, should be operated at full loaddesign conditions and the sight glass at the evaporatorshould be checked. When the sight glass for each circuitclears, compare the temperature of liquid leaving thesubcooler with that leaving the condenser. Thetemperature differernce, subcooling, should be 15°F to20°F.

38

3.0 OPERATION ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.1 Qualified Unit Start-up Report

The unit should be started up only by a refrigerationtechnician who is familiar with accepted operationpractices for refrigeration systems.

Use reciprocating unit start-up report, Form NS1001F,July 1985, to record all temperature, pressure, electricalreadings and control settings. A copy must beforwarded to Dunham-Bush, Inc., North AmericanService, Harrisonburg, Virginia before the warranty willbe honored.

3.2 Typical ACDS-B Refrigerant Piping

ACDS-B 015S thru 030S have a tandem scroll compressorset and a single circuit unit.

ACDS-B 025D thru 1000D have (2) tandem scrollcompressor sets and dual circuit unit

See Figure 3.2A, 3.2B, 3.2C for typical ACDS-B packagedchiller refrigerant piping.

See Figure 3.2D, 3.2E, 3.2F for typical AUDS-Bcondensing unit piping.

NOTE: When the unit is spring mounted, care shouldbe taken to insure that piping is not excessively rigid.See Section 2.6.

39

HP SW (REF.)

LP TRD TYP.

C1B

OR HORIZONTAL.

OUTLET FACING DOWN

C1A

OUTLET FACING DOWN

OR HORIZONTAL.

SC-IN

7/8 ON ALL

FILTER DRIER

HG

(HORIZ)

W/ SOL

REG

HG

IN

VALVE

HAND

OUT

WATER

HP TRD

OUTLET FACING DOWN.

TO BE HORIZONTAL WITH

LOW PART OF LINE. VALVE

NEAR END OF UNIT IN

HAND VALVESMODELS

(VERT)

LIQ.

COND

TEE (DOWN)

LIQ.

HG

CHR

WATER

COND

VALVE

OUTLET FACING DOWN

OR HORIZONTAL

LP TRD TYP.

C2A

OUTLET FACING DOWN

OR HORIZONTAL

C1A

C2B

HAND

HP SW (REF)

HP TRD

C1B

NEAR END OF UNIT IN LOW PART

OF LINE. VALVE TO BE HORIZONTAL

WITH OUTLET FACING DOWN.

FILTER DRIERS

W/ SOL

CHILLER

REGULATOR

HOT GAS

WATER

IN

CIRCUIT 2

OUT

WATER

CIRCUIT 1

TXV's

TXV's

LIQUID CIRCUIT 1

ALL MODELS

HOT GAS

SC-IN

RIGHT HAND

CONDENSER

(HORIZONTAL)

7/8

7/8

LEFT HAND

CONDENSER

(HORIZONTAL)

7/8

(DOWN)

TEE

LIQUID CIRCUIT 2

ALL MODELS

LIQ. LIQ.

SC-IN

RIGHT HAND

CONDENSER

(VERTICAL)

HOT GAS HOT GAS

(DOWN)

LIQ.LIQ.

TEE

LEFT HAND

CONDENSER

(VERTICAL)

HOT GAS

3.0 OPERATION - MECHANICAL SYSTEMS (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

Figure 3.2A Typical ACDS-B 015S-030S Packaged Chiller Refrigerant PipingSingle Tandem Scroll Compressor Set — Single Circuit Unit

Figure 3.2B Typical ACDS-B 025D-100D Packaged Chiller Refrigerant PipingTwo Tandem Scroll Compressor Sets — Two Circuit Unit

40

W/ SOL

OUTLET FACING DOWN

OR HORIZONTAL.

HP SW (REF)

OR HORIZONTAL.

OUTLET FACING DOWN

C1A C1B

VALVE

HAND

HP TRD

LIQ.

HOT GAS

REG

HG

1 1/8

SC-IN

HOT GAS

(HORIZ)

COND

TEE (DOWN)

LIQ.

COND

(VERT)

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

Figure 3.2C Typical AUDS-B 015S-030S Packaged Chiller Refrigerant PipingSingle Tanem Scroll Compressor Set — Single Circuit Unit

Typical AUDS-B 025D-100D Packaged Chiller Refrigerant PipingTwo Tandem Scroll Compressor Set — Two Circuit Unit

Figure 3.2D

022578ABCAT

022577AACAT

41

3.3 Pre-Start-Up Procedure forACDS-B Packaged Chillers &AUDS-B Split Systems

The unit is ready for start-up when the following procedureshave been completed.

1. Water piping for the cooler is installed and tested.

2. Electrical connections are made and properly fused.

3. Unit has been leak tested, leaks corrected, and chargecompleted.

4. Compressor crankcase heater(s) has been energized fora minimum of 24 hours.

5. Calibrated refrigerant gages have been connected to thesuction and discharge pressure ports.

6. Turn on the chilled water pump, check direction ofrotation and adjust the water flow through the coolerto the specified flow rate. Bleed off all entrained air.

7. Manually energize the fan starters and check the fanrotation. Fans should pull air through the condensercoil and discharge vertically upwards. Rotation can bechanged on 3-phase motors by interchanging only twowires on the main terminal block.

8. Check all refrigerant valves to be sure they are open.

9. Scroll compressors, like several other types ofcompressors, will only compress in one rotationaldirection. Three phase compressors will rotate in eitherdirection depending upon phasing of the power. Sincethere is a 50-50 chance of connecting power in such away as to cause rotation in the reverse direction, it isimportant to ensure proper rotation direction isachieved when the system is installed and operated.

There is no negative impact on durability caused byoperating three phase Compliant Scroll compressors inthe reversed direction for a short period of time (underone hour). However, after several minutes of operation,the compressor’s internal protector will trip.

10. Proceed to System Start-up.

3.4 System Start-Up & Reportingfor ACDS-B Packaged Chillers& AUDS-B Split-Systems

1. Request for Start-Up Representative ACDS-B/AUDS-B

Start-up service is an option for these units and is requestedwhen the unit is ordered. If you purchased start-up service,then after the installation has been completed and checked,Form 9180 must be filled out and sent to the local Dunham-Bush representative who sold the unit. Following receiptof this signed form, a representative will be sent to thecustomer. The purchaser should have competent serviceand operating personnel in attendance to assist in the workinvolved, and also to be trained in the operation andmaintenance of this unit.

The representative will inspect the installation to determinewhether it meets Dunham-Bush, Inc. requirements,perform the initial start-up of the installation, determine

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

whether it is in satisfactory operating condition, andinstruct specified customer personnel in its operation andmaintenance for the length of time specified in thepurchase contract.

NOTE: Sump oil heaters should be energized a minimumof 24 hours and the oil sump temperature must be at aminimum of 100°F (38°C) prior to arrival of start-uprepresentative. This will ensure that the oil is warmenough to vaporize any dissolved refrigerant and thatthe oil is within the normal operating temperature range.

Scroll Compressor Rotation

Scroll compressors, like several other types of compressors,will only compress in one rotational direction. Three-phasecompressors will rotate in either direction depending uponphasing of the power to L1, L2 and L3. Since there is a 50/50 chance of connecting power in such a way as to causerotation in the reverse direction, it is important to ensureproper rotation direction is achieved when the system isinstalled and operated. Verification of proper rotationdirection is made by observing that suction pressure dropsand discharge pressure rises when the compressor isenergized. Reverse rotation results in a sound level abovethat with correct rotation direction, as well assubstantially reduced current draw compared totabulated values and after several minutes of operation,the compressor’s internal protector will trip. All three-phase compressors are wired identically internally. As aresult, once the correct phasing is determined for aspecific system or installation, connecting properlyphased power leads to the same terminals shouldmaintain proper rotation direction.

2. Before starting the compressor(s), check all three phasesof supply voltage, of all legs of the motor. They must bewithin ± 10% of the nameplate voltage.

3. Start compressor(s), check the gages and note if thepressures are within the prescribed limits.

4. Check the refrigerant sight glass at the TX Valve to besure it is free of bubbles. If not, charge as specified persection 4.8 Charging.

5. Shut the compressor down and check the compressorshell sight glass for oil level. It should be visible in thesight glass. If not, see Section 3.7 Lubrication.

6. Restart the compressor. After an hour of operation theexpansion valve superheat setting should be checked, itshould be between 10° and 14°F at full load designconditions. In some instances, it will be necessary toraise the superheat setting to prevent expansion valvehunting. Turn the TX valve adjustment stem clockwiseto increase the superheat setting and counterclockwiseto decrease the setting. Be sure and allow 10 minutesbetween each adjustment for the system to rebalance.

7. The electrical control settings should be checked and, ifnecessary, reset to those settings indicated on the wiringdiagram. Safety controls are factory set and must bemaintained at settings indicated on the wiring diagram.

8. The temperatures of the chilled water both in and out,should be checked to insure the unit is operating withinthe desired temperatures.

42

3.6 System Flow Rate ACDS-B

The quantity of chilled water being circulated can beestimated by determining the water pressure drop throughthe cooler and reading GPM from the appropriate pressuredrop curve, Table 3.6A.

An alternate method of determining GPM is to measurepressure difference from pump inlet to outlet and read GPMfrom pump curve.

Water flow rate must not vary more than ± 10% from designflow rate.

3.0 OPERATION - MECHANICAL SYSTEMS (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

NOTES:

1. A constant water flow rate is required with a minimum of3 gallons per ton (3.25 L/kW) water loop volume increasingup to 10 gallons per ton (10.8 L/kW) for process, low loadapplications with small temperature ranges and/or vastlyfluctuating load conditions.

2. AUDS-B 160-270 split system chillers use the same coolersas the ACDS-B 160-270 packaged chillers.

3. AUDS-B 160-270 split-system remote coolers are suppliedinsulated with the refrigeration specialty parts shippedloose for field installation. (No cooler heaters suppliedsince the remote cooler option is intended for indoorinstallation.

3.5 Lubrication ACDS-B/AUDS-B

3.5.1 GeneralAll scroll compressors have an internal system for positivelubrication.

3.5.2 Oil LevelObserve oil during operation to see that oil is visible in thesight glass.

1. There is a Shrader valve fitting at the oil level to removeor add oil if necessary.

2. NOTE: The scroll compressor is a single directioncompressor and must not be run in the reverse direction.

3.5.3 Oil TypeIf the oil becomes discolored indicating contamination, thecontamination can be eliminated by installing a new filter-drier in the liquid line and changing the oil.

WARNING: USE ONLY DUNHAM-BUSH OR COPELANDAPPROVED REFRIGERATION OIL. WARRANTY WILL BE VOID IFOTHER THAN APPROVED OIL IS USED.

Oil charge for a complete recharge is shown in the followingtable. Oil type and approved oils are also listed for thecompressor. After recharge, the oil level should be maintainedvisible in the sight glass.

*Oil charge is total for both compressors of the scroll tandem.

NOTE: To remove contaminated oil from the compressor,first reclaim the refrigerant from the compressor with thecompressor isolated by closing the system shutoff valves.With the compressor at 0 pressure, remove the oil equalizerline at the oil level. Allow the oil to drain into a catch pan. Toremove the remaining oil below the sight glass level, bend a12-inch piece of 1/4 inch plastic tubing to fit thru the openequalizer fitting on the compressor to reach to the bottomof the compressor sump. Seal the opening between the tubingand the equalizer fitting with a rag.

Attach a service manifold to the Schrader fitting on thecompressor housing at the oil level. Insert 1-2 psig of nitrogeninto the compressor using the above Schrader fitting to forcethe oil in the sump out thru the small plastic tube into thecatch pan. Change liquid line filter drier cores using specialacid removing type cores.

Compressor Oil Charge* Oil Type Approved Oils(Ounces)

ZZ18 280 150SUS CALUMET R015thru 280 150SUS orZZ38 280 150SUS TEXACO WF-32

Tandem 280 150SUS "Scrolls 280 150SUS "

TABLE 3.6A

Cooler Curve No. for Table 23

Unit Std Optional Optional

Model CH1 CH2 CH3

Size 44°F(CLR) 42°F (CLR) 40°F (CLR)

015S 1 1 1

020S 1 1 2

025S 3 3 2

027S 3 3 4

030S 4 4 4

025D 3 4 4

030D 3 4 6

035D 5 7 8

040D 5 7 9

045D 7 7 8

050D 9 9 12

055D 9 9 12

057D 9 9 12

060D 12 12 12

065D 11 11 11

070D 11 11 11

080D 11 11 11

090D 12 12 12

100D 13 13 13

43

ENGLISH I.P. AND METRIC S.I. UNITS

WATER SIDE PRESSURE DROP ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

Figure 3.6B

Single Circuit Coolers

Dual Circuit Coolers

Cooler English I.P. Units Metric S.E. UnitsCurveNo. Model *Conn. Size

1 CHS006601B 3" NPTE 29 97 1.83 6.13

2 CHS007601A 3" NPTE 37 101 2.34 6.39

3 CHS007601B 3" NPTE 50 164 3.16 10.38

4 CHS008601A 3" NPTE 56 168 3.54 10.63

3 CHD007601B 3" NPTE 50 164 3.16 10.38

4 CHD008601A 3" NPTE 56 168 3.54 10.63

5 CHD008601B 3" NPTE 70 227 4.42 14.32

6 CHD010601A 4" NPTE 62 205 3.92 12.97

7 CHD010601B 4" NPTE 78 315 4.93 19.23

8 CHD011601A 4" NPTE 69 206 4.37 13.03

9 CHD011601B 4" NPTE 86 304 5.44 19.23

10 CHD013601B 4" NPTE 101 407 6.39 25.75

11 CXD12090F09 4" NPTE 112 365 6.94 22.63

12 CXD12090B07 4" NPTE 140 380 8.68 23.56

13 CXD12120B07 4" NPTE 188 459 11.65 28.45

Minimum Maximum Min. Max.GPM GPM Lit./Sec. Lit./Sec.

TABLE 3.6B

*Non-Metric compliance

DX COOLER:

44

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.7 System ControlACDS-B/AUDS-B

3.7.1 Capacity ControlThe standard system capacity control operates asfollows:

Staging of unit capacity in response to system loadrequirements is controlled by the microcomputer, whichmonitors the leaving water temperature.

ACDS-B/AUDS-B 015S, 020S, 025S and 030S have twosteps capacity control.

ACDS-B/AUDS-B 027S has three steps capacity control.

ACDS-B/AUDS-B 025D to 100D have four capacity controlsteps.

All models are equipped with tandem scroll compressorsper refrigerant circuit and capacity is controlled bycompressor staging.

As the chiller load initially drops, the suction pressureof the compressor(s) starts dropping proportionately,thus balancing minor load variations.

Hot gas by-pass capacity control is used (as an option)to lower the "first on/last off" step of capacity controlto roughly 50%. This effectively provides an additionalstep of capacity control. The use of multiple smallcompressors gives good part load performance energyefficiency ratios (EER). Hot gas by-pass operates byimposing an artificial load on the evaporator. Dischargegas from the compressor is introduced to the liquid-vapor mixture of refrigerant downstream of theexpansion valve. The discharge gas is cooled by theliquid refrigerant present in the turbulence of theevaporator so that the final temperature does not rise.Hot gas by-pass does not offer any energy savings, butdoes allow the cooling capacity of the equipment tovary precisely with the load requirements.

Refer to Table 3.7.2 or Table 3.7.3 to determine thecapacity control scheme for your specific unit.

45

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.7.2 ACDS-B/AUDS-B Capacity Control Staging for Single Circuit Units

NOTE: Hot gas bypass modulates to approximately one-half of the capacity of the first step.

3.7.2 ACDS-B/AUDS-B Capacity Control Staging for Dual Circuit Units

065D 0 13 25 50 75 100

070D 0 15 25 50 75 100

080D 0 14 25 50 75 100

090D 0 14 25 50 75 100

100D 0 16 25 50 75 100

First Stage First Second Fullw/HGBP Stage Stage Capacity

ACDS-B Min. Cap. Single Circuit Single Circuit Single Circuit

& AUDS-B w/HGBP Compressor Compressor Compressor

Unit Model Off Option #1 - On #2 - On #1 & #2 - On

015S 0 25 50 NA 100

020S 0 25 50 NA 100

025S 0 25 50 NA 100

027S 0 23 46 54 100

030S 0 25 50 NA 100

Percent of Full Capacity

Compressor Staging - Single Refrigerant Circuit Units

First Stage First Second Third Fullw/HGBP Stage Stage Stage Capacity

ACDS-B Min. Cap. Compressor Compressors Compressors Compressors

& AUDS-B w/HGBP 1-On Off 1-On 3-On 1, 2-On 3-On 1, 2-On 3, 4-On

Unit Model Off Option Circ. 1 Circ. 2 Circ. 1 Circ. 2 Circ. 1 Circ. 2 Circ. 1 Circ. 2

025D 0 13 25 50 75 100

030D 0 13 25 50 75 100

035D 0 12 24 50 74 100

040D 0 12 23 46 69 100

045D 0 13 25 50 75 100

050D 0 12 24 48 72 100

055D 0 11 22 48 74 100

057D 0 13 25 50 75 100

060D 0 13 25 50 75 100

Percent of Full Capacity

Compressor Staging - Dual Refrigerant Circuit Units

46

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.7.4 Fan Cycling ControlACDS-B/AUDS-B

Fan cycling control is based on the discharge pressureof the refrigerant circuit being cooled by the fans. Seesection 3.9.3.2. The following two versions of fancontrol are used.

1) Standard Unit - Fan Cycling only

2) Low Ambient Option - Combination fan cycling andvariable speed motor control to reach low ambients

NOTE: The variable speed motor is applied in place ofthe motors indicated in Step 1 of the tablebelow and operates as described under SCR insection 3.8.

ACDS-B/AUDS-BFan Cycling Control Chart

ACDS-B/AUDS-B Refrig. Fan Number on at Each Step

Model Circuit 1 2 3 4

1 #1 #2

1 #1 #3

2 #2 #4

1 #1 #3 #5

2 #2 #4 #6

1 #1 #3 #5 #7

2 #2 #4 #6 #8

015S-030S

025D-055D

057D-090D

100D

47

3.8 Electrical Controls DescriptionACDS-B/AUDS-B

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

ChillerLINK - This module converts the communication protocolof the microcomputer to an industry standard protocol.Typically the standard protocols available are BACnet orMODBUS.

CR - Relays (Miscellaneous Control)These relays provide the necessary circuit logicfor lock-in, lock-out and transfer functions.

CT - Current Transformer - This device is used by themicrocomputer to measure the current beingdrawn by a compressor.

CWP - Chilled Water Pump Interlock.It is recommended that an interlock betweenthe chilled water pump and the package beprovided to prevent the unit from operatingwith the chilled water pump off. Connect theinterlock to the terminals shown on thediagram.

FLS - Flow Switch. The chilled water flow switch mustbe installed at the job site to ensure chilledwater flow while the package is in operation.

Gateway - This board converts RS485 information fromthe microcomputer to RS232 data for a modemor PC computer.

GFI - Ground Fault Interrupt - The ground fault sensormonitors the compressor and fan motor currentfor leakage to ground. If the leakage exceedsthe setting of the device (4-12 amps), thecontrol circuit power will be turned off.

HTR - Crankcase HeaterEnergized continuously as long as control circuitpower is on and compressor is off. This heatermaintains crankcase temperature above thesystem temperature during the compressor offcycle, preventing refrigerant migration into thecrankcase and consequent compressor damage.

Chiller Heater and Thermostat (Water Chillersonly)-The chiller heater with integral thermostatis powered by a separate customer supplied115VAC source. The heater turns on when theshell temperature drops to 38°F. This helpsprevent a chiller freeze-up under low ambientconditions.

M - Contactor (Compressor and Fan Motor) Thecontactor, operated by the control circuit,provides power to the compressors and fanmotors. Compressor contactors are used eithersingly or in parallel pairs. These devices areamp rated to handle both rated load amps andlocked rotor amps.

3PS - Compressor Oil Failure Switch (Manual Reset)This is a differential pressure switch thatcontinuously compares oil pressure with suctionpressure to provide protection against low netoil pressure. It is equipped with a 120 secondtime delay feature to avoid nuisance shutdowndue to momentary low fluctuations of oilpressure due to oil foaming, etc.

S1 - Power Switch (115V Control Circuit)This switch energizes the control circuit andmust be left on at all times (except fortemporary control circuit service work) to allowoff cycle pumpdown and normal on cycleoperation. (Compressor sump heaters areconnected before this switch and are notaffected by switch position).

S2 - Unit Enable Switch - This switch selects "ON","OFF", or "Remote" for the unit enable. If set to"ON", the unit will be allowed to providecooling. If set to "OFF", the unit will only startto maintain pumpdown and will not providecooling. When the switch is set to "Remote",an external set of contacts must close to allowthe unit to provide cooling.

S3-S6 Compressor Switch. This switch disconnectspower from the corresponding compressorcontrol circuit. These switches should only beused for service work, since pumpdown isdisabled when switch is off.

SCR - Fan Speed Control (Optional)The fan speed control varies the speed of thefan, depending on head pressure. With thedischarge pressure of 140 psig or below, thefan is at minimum speed. As discharge pressurerises, the fan speed is increased proportionallyuntil it reaches full speed at 200 psig. See fancycling control section.

SOL - Liquid Line Solenoid ValveCloses when the compressor(s) is off to preventany liquid refrigerant from accu-mulating in thechiller during the off cycle.

48

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.9 DB Director MicrocomputerSystem Control

For units with Electronic Expansion Valve option,this valve pulses open to meter refrigerant intothe vessel and maintain desired suctionsuperheat.

Unload Solenoid - This solenoid will unload thecompressor cylinder bank when the solenoid isenergized.

SSR - Solid State Relay Board (Optional) - This boardprovides the pulsing signal to an electronicexpansion valve.

1TAS - Motor Overload ProtectionCompressor overload protection is afforded bysolid state device (1TAS) that monitors internalmotor temperature. If the maximum motortemperature is exceeded, the compressor willshutdown. To reset 1TAS, open the associatedcompressor switch for 5 seconds.

10TR - Timer (Optional) - This timer provides a 1 seconddelay between closing of compressor contactorsfor part wind starting.

UVR - Undervoltage Relay (Optional)Protects the unit from the following electricsupply malfunctions: under-voltage, phasereversal and single phasing. If the UVR trips, acontrol relay will de-energize and open thecontrol circuit. A LED light, located on the UVR,will indicate a normal power supply.

Dunham-Bush ACDS-B/AUDS-B reciprocating packagesare controlled by a microcomputer system. Thecomputer system is composed of a main microcomputerboard (MCB), several types of input/output (I/O) boards,and sensors. The I/O boards are connected to themicrocomputer by RS485 shielded cables. Thesehardware components are controlled by the softwareprogram in the microcomputer. The softwaredetermines the state of the output relays based on theinput values.

There are two types of sensor inputs to the computersystem. A digital input indicates whether or not 5VDCvoltage is present at the input. This could be used todetermine whether or not the unit is enabled, a waterflow switch is made, or the status of other on/offdevices.

Another type of sensor input is an analog input. Ananalog value is one that varies continuously, such as atemperature or pressure. An analog input must beconverted to a digital value before the computersoftware can process the data.

The computer system outputs are relays that switch the115 VAC control devices such as contactors andsolenoids. There are eight outputs on the mainmicrocomputer board and eight outputs on each relayoutput board.

The software for the computer is stored in threedifferent types of computer memory chips. The EPROMchip (Electrically Programmable Read Only Memory)stores general operating procedures (algorithms). TheEEROM chip (Electronically Erasable Read Only Memory)stores the program that defines the configuration for aparticular unit. This software is called the configurator.Both of these chips retain their content when power isremoved. The third type of memory is RAM (RandomAccess Memory) and is battery backed and is used forstoring non-essential information.

3.9.1 PrecautionsThe following precautions must be taken while workingwith the microcomputer system.

1. Cover the computer components completelywhen drilling sheet metal near the computer.

2. Strip wires away from microcomputer toprevent strands from falling on components.

3. Do not allow the component boards to get wet.

4. Route control and power wires away fromRS485 cables and sensor wires.

5. Handle boards with care.

6. Use shielded cables for all digital and analogsensor inputs.

3.9.2 Computer OperationThe keypad and display are used to display data andalter setpoints. The display has 2 lines with 16 charactersper line and the keypad has 16 keys. See figure 3.9.2for the outline of the keypad and display.

49

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

DISPLAY STATUS

7

8

6

51

2

3

4

SYSTEMPRESSURE

COMPRESSORSTATUS

CONDENSORSTATUS

EVAPORATORSTATUS

ALARMSTATUS

SYSTEMTEMPERATURE

ADDITIONTALSTATUS INFO.

LOCKOUTSTATUS

ENTRY

SERVICEDIAGNOSTI

SETPOINTS(SAFETIES)

MANUAL(AUTO)

LOCKOUTRESET

PROGRAMOPTIONS

INCREASE (+)

DECREASE(-)

ENTER

3.9.2 Computer Operation (cont.)The keypad has 8 “DISPLAY STATUS” keys and 8 “ENTRY”keys. The number keys, with corresponding function,are:

1 - COMPRESSOR STATUS

2 - CONDENSER STATUS

3 - EVAPORATOR STATUS

4 - ALARM STATUS

5 - SYSTEM PRESSURE

6 - SYSTEM TEMPERATURE

7 - ADDITIONAL STATUS INFO

8 - LOCKOUT STATUS

The “ENTRY” keys are:

SERVICE DIAGNOSTIC

SET POINTS (SAFETIES)

MANUAL (AUTO)

LOCKOUT RESET

PROGRAM OPTIONS

INCREASE (+)

DECREASE (-)

ENTER

Figure 3.9.2

50

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.9.2.1 Keypad Display Quick Reference --Display Status

To display data from the DISPLAY STATUS keypad, press the desired key to show the first two lines of data.Repressing the same key selects the next two lines, etc. The keypad has 8 numbered “Display Status” keys. Thenumber keys, with corresponding function are:

1 – COMPRESSOR STATUS 5 – SYSTEM PRESSURE2 – CONDENSER STATUS 6 – SYSTEM TEMPERATURE3 – EVAPORATOR STATUS 7 – ADDITIONAL STATUS INFO4 – ALARM STATUS 8 – LOCKOUT STATUS

DISPLAY STATUS

7

COMP1 LOADEDLLS 1 ON

COMP2 LOADEDLLS2 ON

COMP1 ONLLS1 ON

ULS1-1 OFF

COMP2 ON

SP DP OPD AMP82 243 24 46

SP DP OPD AMP83 233 26 57

CHIL OUT +44.8FCHIL IN +54.2F

AMP 1 +46.5AUNIT CTL RUN

CHIL FLW YESCHIL RST +0.0F

AMP2 +57.2A

COMP1 = 1015HSTARTS=0000210

LLS1 = 1010HSTARTS =000200

ULS1-1 = 0080HSTARTS = 00230

1 APR 26 0027:37LOW SUCTION #1

1 5P DP OPD AMP 52 215 25 42

2 APR 24 1025:40NO RUN #2

CHIL OUT 44.8FCHIL IN 54.2F

8

6

51

2

3

4

SYSTEMPRESSURE

COMPRESSORSTATUS

CONDENSORSTATUS

EVAPORATORSTATUS

ALARMSTATUS

SYSTEMTEMPERATURE

ADDITIONTALSTATUS INFO.

LOCKOUTSTATUS

Chiller Configuration Example• Two reciprocating compressors• One unloader solenoid on compressor

#1• One liquid line solenoid per compressor

• Four condenser fans

• Suction & discharge pressure percompressor

• Oil pressure per compressor

• Leaving liquid temperature sensor

• Return liquid temperature sensor

1 APR 26 0028:37LOW SUCTION #1

2 APR 24 1025:4NO RUN #2

3 APR 20 0815:01POWER RETURNED

4 APR 20 0710:20POWER FAILED

FAN 2 ONFAN 4 ON

COND ON OFFSETCIRCUIT #1 φ

COND ON OFFSETCIRCUIT #2 φP

1

2

FAN 1 ONFAN 3 ON

51

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.9.2.2 Keypad Display Quick Reference --ENTRY KEYS

The “ENTRY” keys are:SERVICE DIAGNOSTICSETPOINTS (SAFETIES)MANUAL (AUTO)LOCKOUT RESETPROGRAM OPTIONSINCREASE (+)DECREASE (-)ENTER

ENTRY

#1 CHIL OUT TARGENTR CHG +45.0F

#8 PMP DN CUT INENTR CHG +70.0P

#9 PMP DN COUTENTR CHG +40.0P

#27 CND STG1 ONENTR CHG + 190.0P

#28 CND STG2 OFFENTR CHG + 140.0P

#35 FLA CIRCUIT 1ENTR CHG + 55.0A

#36 FLA CIRCUIT 2ENTR CHG + 65.0A

AUTHORIZATIONENTR CHG OPTION

SENSOR OFFSETSENTR CHG OPTION

SENSOR DIAGNOSTICENTR CHG OPTION

CLEAR ALRM HSTRYENTR CHG OPTION

UNIT INFORMATIONENTR CHG OPTION

CONTROL STATUSENTR CHG OPTION

CLEAR PT INFOENTR CHG OPTION

TIME DISPLAYENTR CHG OPTION

DATE & TIME SETENTR CHG OPTION

DAY OF WEEK SETENTR CHG OPTION

OPERATING SCHEDSENTR CHG OPTION

DATE DISPLAYENTR CHG OPTION

RELAY OUTS MANALENTR CHG OPTION

ANALG OUTS MANALENTR CHG OPTION

SENSOR INS MANALENTR CHG OPTION

RESET LOCKTS?ENTER KEY=YES

ENTER KEYSelects options or enters

changes after adjustmentshave been made.

INCREASE (+)KEY &

DECREASE (-)KEY

Used To adjustvalues or changeoptions selected.

(SERVICE,SETPOINTS,MANUAL, &

PROGRAM keys.)

SERVICEDIAGNOSTIC

SETPOINTS(SAFETIES)

MANUAL(AUTO)

LOCKOUTRESET

PROGRAMOPTIONS

INCREASE (+)

DECREASE(-)

ENTER

52

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.9.2.3 Display Data

To Display Data from the DISPLAY STATUS keys

.1 General Information:• Pressing a key selects the first two lines of

data as shown in Figure 3.9.2.1. Repressingthe same key selects the next two lines, etc.

• The "+" and "_" keys may be used with alarmand lockout status to allow scrolling.

.2 COMPRESSOR STATUS keyThe data from this key is divided into twosections. The first section provides the circuitcontrol state of each of the compressors. Thesecond section is the ON/OFF state of the relayoutputs related to compressor circuit control.

When the button is first pressed, compressor 1state is shown on the first line and liquid linesolenoid or electronic expansion valve status isshown on the second line. Subsequent keypresses display the status for the remainingcompressors. Refer to section 3.9.2.8 for theCircuit Control States. The status for the liquidline is either ON or OFF, whereas for theelectronic expansion valve, the valve percentageof opening and the current superheat value isdisplayed.

After the compressor control states are alldisplayed, subsequent key presses display theON / OFF state of each of the relay outputsrelated to compressor control such ascompressor, liquid line, and unloaders.

.3 CONDENSER STATUS keyThe data from this key is divided into twosections. The first section provides the ON /OFF state of each of the fan control relays. Thesecond section displays the calculated offset tothe fan turn on pressure for each circuit. Thesevalues are labeled "Cond ON Offset" and areadded to the fan turn on setpoint to determinethe actual pressure at which the fan will turnon. See fan control logic description.

.4 EVAPORATOR STATUS keyWhen this key is first pressed, the leaving watertemperature (Chil Out) and the entering watertemperature (Chil In) are displayed. If the chilledwater pump control option is furnished and thekey is pressed again, the On/Off status of thepump and chilled water flow is displayed.

.5 ALARM STATUS keyThe alarm status key displays the most recent32 alarms and lockouts. When the key is firstpressed, the most recent alarm (#1) isdisplayed. The alarm number is displayed inthe upper left corner followed by the month,day, and time of the alarm. The second lineshows the name of the alarm. The Increase(+) and Decrease (-) keys can be used to scrollthrough the alarm listing. See the alarmdescription Section 3.9.2.7.

.6 SYSTEM PRESSURE keyThe system pressure key displays the operatingpressures and amps for each compressor. Thefollowing values are displayed:

1. SP = Suction Pressure

2. DP = Discharge Pressure

3. OPD = Oil Pressure Differential (optional)

4. AMP = Amps of the compressor

When the key is first pressed, these values areshown for compressor 1. Subsequent keypresses display the value of the othercompressors. The compressor number is shownin the upper left corner of the display.

.7 SYSTEM TEMPERATURE keyWhen this key is first pressed, the chiller leavingwater temperature (Chil Out) and chillerentering water temperature (Chil In) values aredisplayed. Subsequent key presses, display allthe sensor input values except the pressures.This includes amps, flow switch, unit controlinput, chilled water reset, and suctiontemperature, if applicable. The sensor inputsrelated to pressure are displayed with theSystem Pressure key.

.8 ADDITIONAL STATUS INFO keyThis key provides the total run hours andnumber of starts for each relay output. Whenfirst pressed, the name of RO #1 (TypicallyComp 1) is shown followed by the total runhours. The second line shows the number ofstarts for that relay output. Subsequent keypresses, scroll through all of the relay outputsand provide the same information.

.9 LOCKOUT STATUS keyThe Lockout Status key is a subset of the AlarmStatus key. Only the chiller setpoint safetyalarms are displayed. These relate to protectingthe machine from abnormal operation. Theinformation displayed for each alarm is thesame as described in the Alarm Status section.

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3.9.2.4 Read and Enter Data

To Read and Enter Data from the ENTRY keys

.1 General Information:Pressing a key selects the first two lines of dataas shown in the Figure 3.9.2.2. Repressing thesame key selects the next two lines, etc.

Different items will appear depending on thepackage configuration, options selected, andauthorization level.

.2 SERVICE DIAGNOSTICS keyThis key cycles through the following menuitems. When the desired menu item is reached,press the ENTER key to display the data.

CONTROL STATUSThis menu item displays the Capacity ControlState and the Evaporator Control State. Thedisplay toggles between these displays everytwo seconds. Refer to the Control StatesSection 3.9.2.8.

AUTHORIZATIONThis menu item is used to enter theAuthorization required to access and makechanges to the microcomputer. When selected,the display shows "ENTER AUTH #XXXX" as aprompt or the four digit code from the numberkeys. As each digit is entered, the Xs changeto 0. When complete, press enter, and theauthorization level is displayed. Four levels ofauthorization are used.

1. VIEW - No authorization is needed to viewdata or reset a lockout.

2. SERVICE - Authorization to access andchange setpoints that are needed for settingup the unit to customer conditions. Typicalauthorization code is #3224.

3. SUPERVISOR - Authorization to access andchange setpoints that are not normallyneeded for configuration of a unit.

4. FACTORY - Allows access to all parameterswith the ability to change the values.

SENSOR OFFSETThis menu item allows sensors to be calibrated.CAUTION: This function should only beperformed by a serviceman with a certifiedaccurate meter. After ENTER is pressed, thesensor can be selected with the Increase/Decrease keys. Then press ENTER again to

adjust the offset value. Use the (+) or (-) keysto change the offset and then press ENTER. Thisoffset value is added to the measured value toobtain the calibrated value used by theprogram.

SENSOR DIAGNOSTICThis menu item displays the analog to digitalconversion counts and the volts for each of thesensor inputs. The conversion varies between0 and 1023, and the volts change between 0Vand 5.012V. Use the (+) or (-) keys to scrollbetween sensor numbers.

UNIT INFORMATIONThis menu item displays the followinginformation. Use the (+) or (-) keys to scrollthrough the data.

• Software version and Configuration number• Hardware version• Unit name• Unit serial number• Model name• Manufacturer• Network address - The network address can

be changed by pressing the ENTER key,followed by (+) or (-) to change the numberand then ENTER.

.3 SETPOINTS (SAFETIES) keyThis key is used to display the setpoints andallows modifications if authorized. When firstpressed, setpoint #1 is displayed. Use the (+)or (-) keys to scroll through the setpoints. Whenthe desired setpoint is displayed, press theENTER key to enter the change mode asindicated by a "+/-" symbol. Use the (+) or (-)keys to alter the setpoint value and then pressENTER when done.

.4 MANUAL (AUTO) keyThis key is used only by authorized servicepersonnel for manual control of the unit.

.5 LOCKOUT RESET keyThis key is used to clear a lockout. Press ENTERafter the safety problem is resolved to reset allrelay outputs to computer control.

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.6 PROGRAM OPTIONS keyThis key displays the following information. Usethe (+) or (-) keys to scroll through the menuitems and then press ENTER to select the desiredscreen.

• DATE DISPLAY - shows the current day ofweek, month, date and year.

• TIME DISPLAY - shows the current day ofweek, and time of day.

• DATE & TIME SET -allows adjustment ofmonth, date, year, hour, and minute. The"+/-" symbol is shown below the field to beadjusted. Use the (+) or (-) keys to changethe field and then press ENTER to move tothe next field.

• DAY OF WEEK SET - allows the day of weekto be changed by pressing the (+) or (-) keys.

• OPERATING SCHEDs - allows the 7 dayoperating schedule to be set up. WhenENTER is pressed, a day of the week isdisplayed followed by the Turn On time andthen the Turn Off time in 24:00 format. Usethe (+) or (-) keys to select the day of weekdesired and then press ENTER. The "+/-"symbol is shown below the field to beadjusted. Use the (+) or (-) keys to changethe field and the press ENTER to move tothe next field.

.7 INCREASE (+) and DECREASE (-) keysThese keys are used to scroll through menus ordata values or to select the desired information.The keys are also used to increase or decreasevalues that are being adjusted. When makingvalue changes, the key may be held down forcontinuous adjustments.

.8 ENTER keyThis key is used to select an option beingdisplayed on the screen or to confirm the newvalue after a data change has been made.

3.9.2.5 Capacity Control States

.1 POWERUPThis state is entered when the microcomputeris powered up or the system has been reset.The system will remain in this state forapproximately 2 minutes with all relay outputsoff. This is a time delay to insure the micro hasstable power before turning any points on andto allow external devices to close.

.2 STOPPEDThis state is entered when the Unit Controlsensor input switch is off. When the chiller isin this state, the individual circuit states if active

are moved to the OFF state through the normalstates. One step of capacity will be decreasedper second.

.3 SCH OFFThis state is entered when the active OperatingSchedule is false. When the chiller is in thisstate, the individual circuit states, if active, aremoved to the OFF state through the normalstates. One step of capacity will be decreasedper second.

.4 EVP FLW (No Evaporator Flow)This state is entered when the flow switchsensor input is OFF. When the chiller is in thisstate the individual circuit states, if active, aremoved to the OFF state through the normalstates. One step of capacity will be decreasedper second.

.5 AMB OFF (Low Ambient Temp Off)This state is entered if the ambient temperaturefalls below the low ambient setpoint. Whenthe chiller is in this state, the individual circuitstates, if active, are moved to the OFF statethrough the normal states. One step of capacitywill be decreased per second. When ambientincreases by 5°F above the setpoint, the unitwill be allowed to run.

.6 LOST IOThis state will be entered whenever themicrocomputer loses communications with anyone of the I/O boards that are connected. Whenthis state is entered, the system will generate aLOST I/O alarm which identifies which I/O is off-line. The LOCKOUT RESET key must be pressedto reset the system, after the LOST I/O has beencorrected. In this state, all RO's except theALARM RO are turned OFF.

.7 LOCKOUTThis state is entered whenever a critical situationis encountered that could cause harm to thechiller package. Items such as freeze protection,low pressure, high pressure or high amps willforce the system into this state. Lockouts canbe reset without authorization from the keypad,however, if the lockout condition has not beencorrected, the system will again be forced intothe LOCKOUT state. In this state, all RO's exceptthe ALARM RO are turned OFF.

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.8 OFFThis state is entered when the system has beencleared from the above shutdown states. Thechiller is now ready to move into an active stateto meet the needed capacity.

.9 HOLDINGThis state is entered when one of threeconditions exists:

1) The liquid being cooled is being maintainedat a temperature in the control zone.

2) The temperature is above the targettemperature plus the control zone but thetemperature is decreasing sufficiently. Thisindicates that the temperature is decreasingtoward the target.

3) The temperature is below the control zonebut the slope is increasing sufficiently. Thisindicates that the temperature is increasingtoward the target. This state indicates thatthere is no need to add or subtract fromthe cooling capacity of the chiller package.This state will be exited when more or lesscapacity is required.

.10 UNLDING (Unloading)This state is entered when less capacity isrequired. During this state a variable time delayis implemented, after which the capacity of thepackage will be decreased by one step.

.11 LOADINGThis state is entered when more capacity isrequired. During this state a variable time delayis implemented, after which the capacity of thepackage will be increased by one step.

3.9.2.6 Circuit Control StatesThe action of the circuit control states actually resultsin more, less or no change in the amount of coolingcapacity. The CAPACITY CONTROL STATES enable theindividual circuits to move within their states.

.1 LOST IOThis state is entered when the CAPACITYCONTROL STATE is LOST IO. This indicates aloss of communication between microcomputerboards. The Lockout reset key will move thecircuit to the OFF state.

.2 LOCKOUTThis state is entered when the CAPACITYCONTROL STATE is LOCK OUT or a safety forthis circuit has indicated that a critical situationhas been encountered. Alarms such as (LOWSUCTION) or (HI DISCH PSI) are examples of a

safety. Lockouts can be reset withoutauthorization from the keypad, however, if thelockout condition has not been corrected, thecircuit will again be forced into the LOCKOUTstate.

.3 PUMP DWN (Pump Down)This state is entered whenever the circuit is nolonger wanted on or if the compressor is offwith chiller flow on and suction pressure risesabove the Pumpdown Cutin setpoint. Thecompressor is on and the liquid line solenoid isclosed. This state is active until the suctionpressure reaches the value in the Pumpdowncutout setpoint. The circuit will then move tothe ANTICYC state.

.4 ANTICYCThis state is entered when the PMP DWN statehas been successfully completed. The circuitwill stay in this state with all circuit points offfor the anti-cycle time delay. The circuit willthen move to the OFF state.

.5 OFFThis state is entered when no cooling capacityis required from this circuit or if the prior statewas holding the circuit off line. In this statethe circuit is ready to attempt to provide coolingcapacity if needed.

.6 UNLDEDIn this state all unloaders on the compressorare on and the compressor is supplying theminimum amount of capacity.

.7 U1 LOADThis state only exists for compressors with twounloaders. This state is in effect when the firstunloader solenoid is off and the secondunloader solenoid is on.

.8 LOADEDThis state is when the compressor is fullyloaded. In this state, the circuit is providingthe maximum amount of cooling capacity.

.9 SUC HLD (Suction Pressure Hold)This state is entered when one unloader hasbeen turned off due to low suction pressure.

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.10 DIS HLD (Discharge Pressure Hold)This state is when a fully loaded circuit that hasmore than one step has encountered adischarge pressure that is close to the highpressure trip. In this state, one step of coolingcapacity will be turned off. The circuit willremain in this state for a minimum of fiveminutes before returning to the LOADED stateif the high pressure condition has beencorrected.

.11 SAFETYThis state is entered when a safety trips but alockout is not to be generated. An alarm isgenerated but the system will restart after atime delay (typically 15 minutes). One safetytrip is allowed every 2 hours. If 2nd trip occurswithin 2 hours of the first trip, then the circuitgoes to the LOCK OUT state.

3.9.2.7 ALARMS SECTION

There are three types of alarms that are generated bythe MCS-8 control logic:

• Information only alarms• MCS-8 system alarms and• Chiller set point safety alarms.

All of the alarms have the same format. The alarm isidentified and it is date time stamped. Alarms can beviewed from the MCS-8 by pressing the ALARM STATUS(4) key or from the PConn program.

3.9.2.7.1 Information only alarms

.1 System generated alarmsThe following alarms are generated to provideinformation. They will not cause a change inthe control algorithm such as a lock outcondition or a relay output being forced off.

• Power Failed• Power Returned• Computer Reset• Battery Failed• LCD Failure• HW Date Invalid• HW Time Invalid• SW Date Invalid• SW Time Invalid• Ram Integrity• Watchdog Reset

.2 Alarms as a result of individual action• Alarms Cleared• STPT Changed• RO Manual• AO Manual

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• SI Manual• Point Info Clear• Clock Set• CFG Downloaded

.3 Alarms generated by the control algorithmThe following alarms indicate that action takenby the control algorithm:

• Rotated Lead• Daylight Savings

3.9.2.7.2 MCS-8 System AlarmsAlarms are generated by the MCS-8 control algorithm:

.1 Configuration problem alarmsThese alarms indicate a problem with theconfiguration file that has been loaded into thesystem. The system is not operational, aconfiguration must be transmitted to the unitform PConn or the config ship must be replacedwith a valid one.

.2 Missing (3) INVALID alarms and description• MCS-RO8 #1 Lost• MCS-RO8 #2 Lost• MCS-RO8 #3 Lost• MCS-SI8 #1 Lost• MCS-SI8 #2 Lost• MCS-SI8 #3 Lost• Lost IO Shutdown

.3 Key sensors problem alarmsThis alarm indicates a problem with a keysensor; it is either shorted or open. The alarmwill contain ALARM followed by the 8 charactername of the sensor.

• Sensor Fault

The following sensors related to the entiresystem are tested:

• leaving liquid, if failed: lock out the chillersystem

• returning liquid, if failed: alarm only, nolock out

• ambient temperature, if failed: alarm only,no lock out

The following circuit sensors are tested. If theyfail, that circuit only is locked out.

• suction pressure and temperature• discharge pressure and temperature• oil pressure and temperature

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3.9.2.7.3 Chiller Setpoint Safety AlarmsThe chiller algorithm incorporates a number of safetychecks to ensure that the various components that makeup the chiller package are not damaged. These typesof safeties are based upon setpoints. If this type ofsafety trips, the circuit or system state becomes SAFETY.The state will remain as SAFETY for a time delay andthen the system will attempt to run. If the system safetytrips for a second time within two hours, the circuit orsystem state becomes LOCK OUT. By this method themicrocomputer attempts to ride through a transientsystem problem while still protecting the chiller package.

.1 Freeze ProtectionIf the leaving liquid temperature drops belowthe "FREEZE TEMP" set point value, the system,and all circuits, will enter a lockout state and afreeze notification alarm will be generated.

.2 No Chiller Flow ProtectionIf the chiller flow sensor input turns off and aliquid line solenoid output stays ON, all circuitswill be locked off and a No Flow alarm will begenerated.

.3 Low Differential Oil Pressure (optional)If the oil differential pressure drops below thelow oil setpoint value, and it remains there forthe time specified in the safety time of that setpoint, the circuit will be locked out and a lowoil alarm generated. This safety is active onlywhen the compressor is on.

.4 Low Suction PressureIf the suction pressure drops below the LowSuction set point value, and it remains therefor the time specified as follows, the circuit willbe locked out and a low suction alarmgenerated. If the unit does not have an ambienttemperature sensor, the low pressure time delayis two minutes from the time that thecompressor starts. If the unit does have anambient temperature sensor and ambient isabove 40°F, the time delay is also two minutes.Below 40°F, however, the time delay atcompressor start is extended to four minutes.After this initial time delay, the delay beforelockout is 45 seconds from the time that suctionpressure falls below the setpoint.

.5 High Discharge PressureIf the discharge pressure rises above the HIDISCH PSI set point value and it remains therefor one second, the circuit will be locked outand a high discharge alarm generated.

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.6 Hi Motor AmpThe full load amps (FLA) of each compressorare stored in FLA COMP # setpoints. If thecompressor amps sensor input rises above theFLA setpoint times the HI AMP % setpointdivided by 100 for 10 seconds, the circuit willbe locked out and a high motor amp alarmgenerated.

.7 No Compressor Proof (No-Run Alarm)If the microcomputer relay output forcompressor control is ON but the amps sensorinput measures a value less than the FLAsetpoint times the LO AMP % setpoint dived by100 for 2 seconds, the compressor is lockedout and No Comp Proof alarm is generated.Typical value for the LO AMP % setpoint is 20%.

.8 Unsafe Suction PressureIf the suction pressure falls below the UnsafeSuction setpoint (typically 10 psig) for 10seconds, the affected circuit will be locked off,and an Unsafe Suction alarm will be generated.

.9 Pumpdown AlarmIf a pumpdown (Compressor ON with liquid linesolenoid OFF) requires more time to completethan the Pump Down Delay (PMP DN DLAY)setpoint, then the circuit will be locked off. APumpdown alarm will be generated.

.10 No-Stop AlarmIf the computer commands a compressor toturn OFF but the amp feedback stays higherthan the LO AMP % setpoint times thecompressor FLA setpoint divided by 100, for 5seconds, then the entire unit will be locked offand the control power relay will be turned off.A No-Stop alarm will be generated.

.11 Low Discharge PressureIf discharge pressure is below the LO DISC PSIsetpoint for 30 seconds while the compressoris operating, the circuit will be locked off on aLow Discharge pressure alarm.

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3.9.2.8 Control States Quick Reference - Chiller ApplicationsControl States tell the user what the system is doing, this information is critical in determining the chiller’s status!

System Reset or Power Returned (delayof 120 seconds or set point value)

Chiller is off because Unit Control sensorinput is in STOP

Unit schedule of operation is holding theunit OFF.

Chiller is off because Chiller Flow sensorinput status is NO.

Chiller is off because Ambient Temp isbelow Low Ambient setpoint

Lost communication to other boards.Chiller is locked out.

Chiller locked out, all points except alarmpoint are OFF.

System ready to run but no coolingcapacity required

Unit running with no change in capacityrequired.

Count down to reduce capacity

Count down to increase capacity

State Description

POWERUP

STOPPED

SCH OFF

EVP FLOW

AMB OFF

LOST IO

LOCKOUT

OFF

HOLDING

UNLDING

LOADING

Lost communication

Safety tripped twice within half hour,circuit locked off

Capacity control state is STOPPED

Pumping down

Delay after turning off circuit

Circuit ready but not required

Compressor ON, all unloaders OFF

1st unloader is OFF, 2nd unloader is ON

Circuit is fully loded, all unloaders areOFF

Holding 1 unloader off until suctionpressure returns to normal

Holding 1 unloader off until dischargepressure returns to normal

Safety tripped not LOCKOUT

State Description

LOST IO

LOCKOUT

STOPPED

PMP DWN

ANTICYC

OFF

UNLDED

U1 LOAD

LOADED

SUC HLD

DIS HLD

Capacity Control States Circuit Control States

SAFETY

Circuit is locked out

Liquid line solenoid (LLS) is closed

LLS is closed with compressor ON to

pumpout liquid

Electronic expansion valve (EXV) is instart-up mode

Liquid line solenoid is open

EXV is holding at desired opening

EXV is opening

EXV is closing

EXV is closing quickly because superheatis low

State Description

LOCKOUT

CLOSED

PREPUMP

STARTUP

OPENED

HOLDING

OPENING

CLOSING

LOW SPR

Evaporator Control States

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3.9.3 Control Functions and OperationsThe computer system performs the following controlfunctions on scroll compressor packages.

1. Compressor Staging 2. Fan control 3. Pumpdown control 4. Anti-recycle timing 5. Lead/lag (optional) 6. Chilled water reset 7. Customer control interlock 8. Low pressure unload 9. High pressure unload10. High amp unload (optional)11. Low ambient temperature limit (optional)12. Power up delay13. Electronic expansion valve control (optional)

A description of each of these functions follows:

3.9.3.1 Compressor StagingRefer to Section 3.7.2 for standard capacity controlstaging and to Section 3.7.3 for optional capacitycontrol staging for a particular unit.

A delay between different compressors starting isimplemented to minimize current inrush and to ensurethat additional capacity is required.

.1 Chiller or DX Coil Control Based on LeavingTemperature

For chiller control or leaving air DX coil control,the computer stages the compressors based onleaving water or air temperature. The controlzone (+) and control zone (-) setpoints arestored in the computer as a temperature offsetfrom desired leaving water or air temperature.The control zone (+) setpoint is where the nextstage of capacity is added, and the control zone(-) setpoint is where the unit capacity isdecreased by one step. If water temperature isfalling at a substantial rate, the unit may stoploading or may decrease capacity beforereaching the control zone (-) setting. After astage transition, a time delay is activated duringwhich another stage transition is not allowed.This lets the system stabilize.

The difference between the control zonesetpoints should be more than the temperaturechange caused by one stage transition toprevent short cycling. Typical control zonesetpoints for a water chiller are control zone(+) = 3.0 and control zone (-) = -2.0. Setpointsfor an air DX coil should be much wider, possiblycontrol zone (+) = 6.0 and control zone (-) = -6.0. In this case, the effect of one stagetransition must be less than 12.0°F at minimumair flow to avoid short cycling.

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Before the first stage of a package is allowedto start, the leaving temperature must be abovethe setpoint by the amount stored in the StartDeadband setpoint. This value may be 3°F fora water chiller but may need to be much higherfor a DX coil, possibly 15°F.

Some air handler configurations require anentering air enthalpy sensor to enable/disablethe unit. When enthalpy is above the EnthalpyStart setpoint, the unit is allowed to start andthen maintain desired leaving air temperature.If the entering air enthalpy falls below theEnthalpy Start setpoint minus a smalldeadband, the unit is disabled.

.2 DX Coil Control Based on Return AirTemperature or Enthalpy

The computer stages the compressors based onreturn air temperature or enthalpy. The stage1 shutdown setpoint is stored in the computeras an offset from desired return air temperatureor enthalpy. The stage deadband setpointdefines the On to Off differential for each stage.The inter- stage deadband setpoint defines thedifferential between the turn OFF points of eachsequential stage. A typical setpointconfiguration for a unit with return airtemperature staging is:

SetpointReturn Air Temp 76.0Stage 1 off -4.0Stage Deadband 2.0Inter-stage D/B 1.5

Stage 1 would turn on at a return airtemperature of 76 + (-4.0) + 2.0 = 74.0°F andwould turn off at 76 + (-4.0) = 72.0°F. Stage 2would turn on at a return air temperature of76 + (-4.0) + 1.5 + 2.0 = 75.5°F and wouldturn off at 76 + (-4.0) + 1.5 = 73.5°F, etc.

.3 Suction Pressure Control

Suction pressure control may be needed for asystem with two DX coils serving separate airflows. The building control system must supplya contact closure to enable/disable eachrefrigerant circuit. When the contact is closed,the first compressor on the unit will start andstay on until the contacts open. The unloaderand/or second compressor will be staged basedon a circuit suction pressure setpoint and acontrol zone around that setpoint. The controlzone staging will operate similarly to thedescription in item 1 of this section.

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3.9.3.2 Fan ControlThe fan control is based on the discharge pressures ofthe circuits being cooled by the fans. Refer to section3.7.4 for a correlation of refrigerant circuit to fannumbers for each model. The computer calculates thehighest discharge pressure of the compressors operatingand uses this value to control fans according to the fanpressure setpoints and the internally calculated fan turnon offset.

The Condenser Stage 1 ON setpoint plus the Fan TurnON offset is where fan 1 turns on. The Fan Turn ONoffset is normally 0.0 and is only increased if a fan shortcycles. The effect of this is to automatically widen theon to off differential and reduce fan cycling. TheCondenser Differential ON setpoint defines thedifference between each subsequent fan turn ONpressure. For example: COND Stage 1 ON = 190.0Psig, Fan Turn ON offset = 20.0, and COND DifferentialON = 10.0.

Then Fan stage 1 turn on pressure is 190 + 20 = 210,Fan stage 2 turn on pressure is 190 + 20 + 10 = 220,and Fan stage 3 turn on pressure is 190 + 20 + (2 * 10)= 230, etc.

The Condenser Stage 2 OFF setpoint is where fan 2 turnsoff. The Condenser Differential OFF setpoint definesthe difference between each subsequent fan turn OFFpressure. For example: COND stage 2 OFF = 140 Psig,and COND Differential OFF = 10.0. Then Fan stage 2turn off pressure is 140, Fan stage 3 turn off pressure is140 + 10 = 150, and Fan stage 3 turn off pressure is140 + (2 * 10) = 160, etc.

Condenser Stage 1 turns OFF only if suction pressurefalls below the low suction pressure setpoint for 10seconds and discharge pressure is less than the Fan stage1 turn on pressure.

A compressor must be operating (amps aboveminimum) for the fans to operate.

3.9.3.3 Pumpdown ControlWhen the water temperature does not require coolingor if the unit enable sensor input contacts are open thecomputer maintains a cooler pressure lower than thePumpdown CUT IN setpoint. When suction pressureexceeds the pumpdown CUT IN setpoint, thecompressor is turned on without activating the liquidline solenoid or electronic expansion valve. Then, whenthe suction pressure falls below the Pumpdown CUTOUT setpoint, the compressor is turned off. Thecompressor control state displays PMP DWN when thecompressor is pumping down. A pumpdown will onlybe performed once every 10 minutes as long as chilledwater flow is on.

When chilled water is not flowing, a maximum of twopumpdowns will be performed after which the unit willremain in the OFF state. The pumpdown process ismonitored to protect the cooler. The pumpdown alarmwill lock off the compressor if the pumpdown requiresmore than thirty seconds to complete. This usuallyindicates a faulty liquid line solenoid.

3.9.3.4 Anti-Recycle TimingWhen a compressor is stopped by the computer, a 5minute time delay is initiated during which thecompressor cannot start. A delay is also implementedwhen power is first applied to the computer.

The compressor control state displays ANTICYC whenthe anti-recycle timer is timing.

3.9.3.5 Lead/Lag (optional feature)A factory installed lead/lag option allows the computerto automatically rotate the lead refrigerant circuit. Thefirst compressor of each refrigerant circuit (compressors1 and 3 of a four compressor package) on the unit musthave an unloader for lead/lag to operate. The leadrefrigerant circuit will rotate whenever a refrigerantcircuit shutdown is required or if the time of day passesthrough midnight. The effect is that the first refrigerantcircuit to become active is the first to shut down.

3.9.3.6 Chilled Water/Air ResetThe chilled water/air reset (CHIL RST) sensor input allowsthe customer to raise the leaving water or airtemperature setpoint based on an external signal.

A 0-5VDC signal can be used, where 0VDC is no resetand 5VDC is maximum reset. The maximumtemperature reset can be defined by setting the MAXTRGT RST setpoint to the maximum temperature resetdesired. For example, to obtain a maximum reset of6°F, a 6.0 is stored in MAX TRGT RST.

CAUTION: The voltage input must never exceed 5.0VDC.

3.9.3.7 Customer Control InterlockCustomer supplied time clock (or other on/off logic)control contacts can be used to control the package.The wiring diagram specifies the place to wire thecontrol contacts. The control contacts signal a sensorinput. If the contacts open, the unit will perform apumpdown if needed and then turn off.

Note: This control must be used for automatic controlof the package. Do not use the flow switch to controlthe package.

61

3.9.3.8 Low Pressure UnloadAfter the initial start-up, if a refrigerant circuitexperiences a low pressure condition and the circuitcan be unloaded, the circuit will enter a low pressureunload mode. If a compressor on the circuit has anunloader, the unloader will be energized. The circuitcontrol state will display SUC HLD (suction hold).

The unit stays in this condition for the safety delay timeand then reverts to normal operation.

Caution: If this mode of operation repeats, the unitrequires service by a qualified refrigeration technician.

3.9.3.9 High Pressure UnloadIf an operating circuit discharge pressure approachesthe high pressure trip point (typically at 355 psig), andthe compressor has an unloader, the unit will enter ahigh pressure unload mode. The unload solenoid willbe energized. This will help prevent a high pressuretrip. The circuit control state will display DIS HLD(discharge hold).

The unit will stay in this mode for the safety delay timeand then revert to normal operation.

Caution: If this mode of operation occurs, the unitshould be checked immediately for condenser blockage.Otherwise, contact a qualified refrigeration technicianfor service.

3.9.3.10 High Amp Unload (Load Limit)The high amp limit is determined by multiplying the HIAMP % setpoint by the FLA setpoint for the compressorand then dividing by 100. If a compressor's ampmeasurement reaches the high amp limit, and thecompressor has an unloader, the unit will enter a highamp unload mode. The unloader will be activated tounload the compressor. The circuit control state willdisplay AMP HLD (amp hold).

The unit will stay in this mode for the safety delay timeand then revert to normal operation. This mode isnormal if the unit is started with high chiller watertemperature.

Caution: If this mode of operation occurs with chillertemperature near design conditions, the unit shouldbe checked immediately for condenser blockage orabnormal system voltage. Otherwise, contact aqualified refrigeration technician for service.

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.9.3.11 Low Ambient Temperature Limit(optional)

If the ambient temperature drops below the LowAmbient setpoint, the compressors will be put into anAMB OFF state and will not be allowed to run. Theambient temperature must rise 5°F above this setpointbefore the unit will be enabled.

3.9.3.12 Power-up Delay

When power is first applied to the controls, a twominute delay is implemented before a compressor isallowed to start. This allows all external devices to time-out and close their contacts.

3.9.3.13 Electronic Expansion Valve Control(optional)

When a compressor starts, the microcomputer controlsthe electronic expansion valve to maintain the desiredsuperheat (typically 12°F). The expansion valvepercentage of opening and current superheat value aredisplayed on the second line of the Compressor Statusdisplay.

3.9.4 General Servicing ProcedureA general troubleshooting procedure is shown below.

(1) Check compressor status to see if it is lockedoff.

(2) If locked off, check alarms to see cause.(3) Check all sensor inputs for accuracy.(4) Repair mechanical system problem or

electrical system problem.(5) Reset alarm by pressing LOCKOUT RESET KEY

followed by ENTER.(6) Check that all requirements for start-up are

met.(7) Operate machine over full operating

conditions and observe results.(8) Verify that all sensor input values are correct.

62

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.9.5A Typical Power Wiring Diagram (Four Compressor Model)

024098AACAT

63

3.9.5B Typical Control Wiring Diagram (Four Compressor Model)

024099ACCAT

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

64

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.9.5B Typical Control Wiring Diagram (Four Compressor Model) (cont.)

024099BCCAT

65

3.10 CircuitOperation for ACDS-B orAUDS-B Split-System Chillersor AUDS-BLeaving Air Controlfor DX Coil

Typical 2 compressor control sequence of operation with4 steps of capacity control. Refer to 3.9.5B for wiringdiagram.

3.10.1 Unit on standbyMain field disconnect switch closed. 115VAC controlpower on. S1 control switch on. Compressor switcheson. Leaving water or air temperature below leavingtemperature setpoint plus Control Zone + setpoint orunit control contacts open.

Pumpdown during standby --

When the flow switch is ON, any of the compressorsmay come on for a short time and pump down if thereis any low side pressure build up during the standbyperiod. Compressors will be held off line for 10 minutesafter a pumpdown. Immediately following a normal"on" cycle, pumpdowns can be expected as residualliquid in the low side vaporizes.

3.10.2 Run cycle sequence (increaseload)

Water or air flow switch closes and unit control contactsare closed.

3.10.2.1 - STEP 1.1 Leaving water or air temperature rises above

chiller out temperature setpoint plus ControlZone + setpoint.

.2 Anti-cycle timer times out or inter-stage delaytimes out and RO1 closes (up to a 5 minutedelay).

.3 Compressor #1 starts thru RO1. Amp sensor,1CT, indicates current flow. RO2 energizesliquid line solenoid 1SOL and circuit 1refrigerant flow starts. Oil failure switch 3PS-1starts to time open (120 sec. delay). Lowpressure lockout starts to time open (120 sec.delay).

NOTE: If either oil pressure or suction pressureis not establishing at a normal level within theabove times, circuit 1 will shut down.

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

.4 Compressor #1 unload solenoid is energizedthrough RO3.

.5 Compressor #1 oil and suction pressure rise tonormal levels, and 3PS-1 terminates the timeopen sequence.

1st stage capacity is now On-Line.


chiller out setpoint plus Control Zone + setpointand stage 1 has been on line for an inter-stagedelay. Compressor #1 unload solenoid is de-energized to LOAD the compressor.

2nd stage capacity is now On-Line.


chiller out setpoint plus Control Zone + setpointand stage 2 has been on line for an inter-stagedelay.

.8 Compressor #2 starts 100% loaded. Ampsensor 2CT indicates current flow. Themicrocomputer energizes liquid line solenoid 2and circuit 2 refrigerant flow starts. Oil failureswitch 3PS-2 starts to time open (120 sec.delay). Low pressure lockout starts to time open(120 sec. delay).

NOTE: If either oil pressure or suction pressureis not established at a normal level within theabove delay times, circuit 2 will shut down.

.9 Compressor #1 unload solenoid is energizedto unload the compressor.

.10 Compressor #2 oil and circuit #2 suctionpressures rise to normal levels, and 3PS-3terminates the time open sequence.

3rd stage capacity is now On-Line.


setpoint plus Control Zone + setpoint and stage3 has been on line for an inter-stage delay.Compressor #1 unload solenoid is de-energizedto load the compressor.

100% capacity is now On-Line.

66

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.10.3 Run cycle sequence (decreasingload)

3.10.3.1 - STEP 4.1 Leaving water or air temperature falls below

chiller out setpoint minus Control Zone -setpoint and stage 4 has been on line for aninter-stage delay. Compressor #1 unloadsolenoid is energized to unload the compressor.



chiller out setpoint minus Control Zone -setpoint and stage 3 has been on for an inter-stage delay. Liquid line solenoid for circuit 2 isde-energized and circuit 2 refrigerant flowstops. Compressor #2 remains running andcircuit 2 pumpdown begins.

.3 When suction pressure drops to the pumpdowncutout setpoint, compressor #2 stops. Circuit#2 pumpdown and unload sequence is nowcomplete, and all circuit 2 controls are back tostandby status.

.4 Compressor #1 unload solenoid is de-energizedto load compressor #1 back to full capacity.



chiller out setpoint minus Control Zone -setpoint and stage 2 has been on line for aninter-stage delay. Compressor #1 unloadsolenoid is energized to unload the compressor.



chiller out setpoint minus Control Zone -setpoint and stage 1 has been on for an inter-stage delay. Liquid line solenoid for circuit 1 isde-energized and circuit 1 refrigerant flowstops. Compressor #1 remains running andcircuit 1 pumpdown begins.

.7 When suction pressure drops to thepumpdown cutout setpoint, compressor #1stops. Circuit #1 pumpdown and unloadsequence is now complete, and all circuit 1controls are back to standby status.

67

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

Unit is off.

3.11 CircuitOperation for AUDS-B withSupply Air Temperature orEnthalpy Control for DX Coil

Typical 2 compressor control sequence of operation with4 steps of capacity control. Refer to 3.9.5B for wiringtypical diagram.

3.11.1 Unit on standbyMain field disconnect switch closed. 115VAC controlpower on. S1 control switch on. Compressor switcheson. Return air temperature or enthalpy below desiredreturn air value plus the stage 1 Off setpoint or unitcontrol contacts open.





3.11.2.1 - STEP 1.1 Return air temperatue or enthalpy rises above

return air setpoint plus Stage 1 Off setpoint plusStage Deadband setpoint.




.4 Compressor #1 unload solenoid is energized

through RO3.



3.11.2.2 - STEP 2.6 Return air temperature or enthalpy rises above

return air setpoint plus Stage 1 Off setpoint plusStage Deadband setpoint plus Inter-stageDeadband setpoint and stage 1 has been online for an interstage delay. Compressor #1unload solenoid is de-energized to LOAD thecompressor.



return air setpoint plus Stage 1 Off setpoint plusStage Deadband setpoint plus two times theInter-stage Deadband setpoint and stage 2 hasbeen on line for an interstage delay.







return air setpoint plus Stage 1 Off setpoint plusStage Deadband setpoint plus three times theInter-stage Deadband setpoint and stage 3 hasbeen on line for an inter-stage delay.Compressor #1 unload solenoid is de-energizedto load the compressor.


68

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○


3.11.3.1 - STEP 4.1 Return air temperature or enthalpy falls below

return air setpoint plus Stage 1 Off setpoint plusthree times the Inter-stage Deadband setpointand stage 4 has been on line for an inter-stagedelay. Compressor #1 unload solenoid isenergized to unload the compressor.



return air setpoint plus Stage 1 Off setpoint plustwo times the Inter-stage Deadband setpointand stage 3 has been on for an inter-stage delay.Liquid line solenoid for circuit 2 is de-energizedand circuit 2 refrigerant flow stops. Compressor#2 remains running and circuit 2 pumpdownbegins.





return air setpoint plus Stage 1 Off setpoint plusthe Inter- stage Deadband setpoint and stage2 has been on line for an inter-stage delay.Compressor #1 unload solenoid is energizedto unload the compressor.



return air setpoint plus Stage 1 Off setpoint andstage 1 has been on for an inter-stage delay.Liquid line solenoid for circuit 1 is de-energizedand circuit 1 refrigerant flow stops. Compressor#1 remains running and circuit 1 pumpdownbegins.


Unit is off.

69

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

3.12 CircuitOperation for AUDS-B withMultiple EvaporatorsControlled by SuctionPressure at the Unit

Typical 2 compressor control sequence of operation with4 steps of capacity control. Refer to 3.9.5B for wiringdiagram.

3.12.1 Unit on standbyMain field disconnect switch closed. 115VAC controlpower on. S1 control switch on. Compressor switcheson. Return air temperature or enthalpy below desiredreturn air value plus the Stage 1 Off setpoint or unitcontrol contacts open.





3.12.2.1 - STEP 1.1 Building control system closes circuit 1 start

contact.




.4 Compressor #1 unload solenoid is energized

through RO3.



3.12.2.2 - STEP 2.6 Circuit 1 suction pressure rises above the

Suction Pressure setpoint plus Control Zone +setpoint and stage 1 has been on line for aninter-stage delay. Compressor #1 unloadsolenoid is de-energized to LOAD thecompressor.


3.12.2.3 - STEP 3.7 Building control system closes circuit 2 start

contact.






3.12.2.4 - STEP 4.11 Circuit 2 suction pressure rises above the

Suction Pressure setpoint plus Control Zone +setpoint and stage 3 has been on line for aninter-stage delay. Compressor #1 unloadsolenoid is de-energized to load the compressor.


70

3.0 OPERATION (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○


3.12.3.1 - STEP 4.1 Circuit 2 suction pressure falls below the Suction

Pressure setpoint minus Control Zone - setpointand stage 4 has been on line for an inter-stagedelay. Compressor #1 unload solenoid isenergized to unload the compressor.


3.12.3.2 - STEP 3.2 Building control system opens Circuit 2 start

contact.




3.12.3.3 - STEP 2.5 Circuit 1 suction pressure falls below the Suction

Pressure setpoint minus Control Zone - setpointand stage 2 has been on line for an inter-stagedelay. Compressor #1 unload solenoid isenergized to unload the compressor.


3.12.3.4 - STEP 1.6 Building control system opens Circuit 1 start

contact.


Unit is off.

71

4.0 MAINTENANCE○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

4.1 GeneralAs with all mechanical equipment, a program of regularinspection, cleaning and preventive maintenance by trainedpersonnel will contribute greatly to the long satisfactoryservice life of this product.

4.2 Periodic InspectionRead essential temperatures and pressures periodically to seethat they indicate normal operation. It is a good idea torecord these readings on a log sheet. See sample, Section4.10. If any abnormal operation is observed, try to determinecause and remedy it. See Troubleshooting Guide, Section4.9.

4.3 Monthly InspectionWipe down external surfaces of unit. Shut unit down, openmain disconnect, inspect control panel, checking for loosewires, burned contacts, signs of overheated wires, etc. Restartunit and check performance of controls. Check sight glassesfor proper refrigerant charge.

4.4 Vessel Maintenance

4.4.1 GeneralThe efficient performance of the cooler and condenser heattransfer surfaces is essential for efficient performance of yourpackaged water cooling machine. If these surfacesaccumulate a film of dirt, scale or slime, their performanceefficiency will degrade substantially. The refrigerant side ofheat transfer surfaces does not foul, since refrigerant is agood solvent and it is in a closed, filtered cycle. Water sidesurfaces can foul from the water system. A program of watertreatment can slow the rate of fouling on heat transfersurfaces, but not eliminate it.

4.4.2 Cooler Cleaning ACDS-B orSplit-System Chiller

The effects of fouling can be detected by recording full loadperformance data on the log sheet. If the difference betweenthe leaving water from the cooler and the saturated suctiontemperature at the compressor is greater than the differencerecorded at clean conditions, the tubes should be cleaned.It is generally advisable to clean the cooler water side surfacesat least annually, and more often if severely foul water isused. This cleaning must be done chemically.

In chemical cleaning, a caustic solution is pumped throughthe heat exchanger, which attacks dirt, slime and mineraldeposits and flushes them away. Chemicals can berecommended by water treatment specialists, but it isimportant to rinse the system thoroughly after cleaning toremove the chemicals before they attack the metal surfaces.The cooler water side (shell side) cannot be physically cleanedbecause of the cross-flow baffle construction.

4.5 Air Cooled CondenserCleaning ACDS-B/AUDS-B

The face of the condenser should be cleaned at least once amonth during operation. If conditions are bad the condenserspick up dirt very quickly, it is suggested that they be cleanedmore frequently. If the condenser is allowed to get too dirty,the unit will run a high head pressure and will not givesatisfactory performance.

Dirty coils can be cleaned using a soft brush or by flushingwith cool water or commerically available coil cleaners. DONOT USE HOT WATER OR STEAM. To do so will cause excessivepressure in the system. The face of the condenser should becleaned at the beginning of the season and periodicallythereafter if conditions require.

4.6 Electrical MalfunctionThe unit has four devices designed to protect compressormotors and motor controllers from electrical malfunction:customer supplied short circuit protection, circuit breakers(optional, if available), under voltage relays (optional), solidstate motor over temperature protectors, and microcomputerhigh amp protection.

If the undervoltage relay trips, it is a sign of trouble inincoming power. If it trips again after resetting, call yourelectric utility to investigate the problem. If circuit breakeror motor over temperature protectors trip, this is a sign ofpossible motor trouble. DO NOT reset and try to runcompressor again. Call authorized service representative tocheck for motor trouble. Resetting these safety devices andrepeated starting could turn a minor motor problem into acostly major motor burnout.

72

4.0 MAINTENANCE (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

4.7 Compressor MaintenanceThe Discus compressor has four components that maybe replaced. The components are the suction strainer,oil pump, cylinder heads and valve plates.

If a component, other than that listed below, fails, thecompressor will require replacement. Return thecompressor to your local Copeland distributor forreplacement.

Compressor Bolt Torque SpecificationsAll Torques in ft.-lb.

DiscusBottom plate 33

Housing cover 33

Oil pump to housing cover 21

Cylinder head 42-50

Oil screen cover 50

Crankcase heater plug 38

Discharge valve 42

Suction valve 1/2" 42

Suction valve 5/8" 80

Capacity control valve 35

Pipe plug, 1/4" 23

Pipe plug, 1/8" 17

Oil sight glass 3

4.8 Refrigerant ChargeAll packaged chiller units are given a complete chargeof refrigerant at the factory. The type and amount ofrefrigerant required is in Physical Specifications. Thetotal refrigerant shown is for the entire system. Sincethese units have separate circuits, each circuit shouldbe considered separately for charging.

In order to check proper refrigerant charge, look in eachliquid line sight glass with the aid of a flashlight duringsystem operation. At all operating conditions, the sightglass should be clear. If bubbles are visible at anyoperating condition, the circuit is short of charge.

Be careful not to overcharge the machine. Overchargingwill result in considerable liquid logging in thecondenser, and excessive condensing pressure.

To add refrigerant, connect a refrigerant vessel to the1/4" backseating port of the suction valve. Purge theair from the tube with refrigerant gas before connecting.With the unit running, open the refrigerant vessel vaporconnection slightly. If the refrigerant vessel is warmerthan the cooler, refrigerant will more readily flow fromthe vessel into the unit.

To determine the proper refrigerant charge, check theamount of subcooling at design full load conditions, ifpossible. The amount of subcooling at the liquid line(liquid line saturation temperature corresponding toliquid line pressure minus liquid line temperature)should be between 15°F and 20°F.

Subcooling at the condenser out-subcooler inlet trapshould not exceed 5°F. This sight glass should be clearwith no bubbles.

73

1. Power off.

2. Main line open3. No control voltage4. Loose terminals

5. Control circuit open

6. Incorrect phase sequence (UVR option)

7. Microcomputer safety lockout

(if applicable)

1. Low voltage

2. No power on one phase of 3 phaseunit

3. Faulty starter or contactor

Check main disconnect switchCheck main fusesCheck control terminal block for 115VACTighten all terminalsCheck fuses, control switches and field installed interlocks, pressure andtemperature controls and readouts.

Reverse incoming power sequence

Resolve problem and press RESET

a. Check at main entrance and at unitb. Consult power company if voltage is low and increase wire size to

the unit if voltage is normal at main and low at unit. Voltage mustbe within 10% of motor nameplate rating.

Check fuses and wiring

Check the contacts and time delay on part wind start (if applicable)

4.9.2 Compressor hums but does not start

1. Refrigerant shortage Check for leaks and add refrigerant

2. No load on chiller Check pump operation and water flow3. Restriction in liquid line a. Plugged filter drier. If temperature drop exists across the drier,

remove and replace cores.b. Liquid line or suction valve partially closed. Open valves fully and

close in one full turn.c. Expansion valve clogged or inoperative. Check superheat setting.

Check charge and thermo bulb.4. Head pressure too low Possible cause - fan cycle switches set too low. Remedy - check and

reset

1. Compressor discharge valve partially Open valve fully and close with one turnclosed

2. Air in system Purge condenser coils3. Overcharge of refrigerant Purge system while in operation until bubbles show in sight glass. Close

valve and add small amount of refrigerant until sight glass just clears4. High pressure control improperly set Adjust the control5. Condenser fan inoperative Check, replace or repair set screw (pulley), fan motor, or inoperative fan

control6. Dirty condenser Clean condenser surfaces with brush and/or vacuum7. Fan cycle settings incorrect Check and re-adjust8. Fan motors not running Check contactor, check motor, check capacitor (if single phase)9. Fan motor reverse rotation Reverse two fan motor leads (3 phase only)

4.9.1 Unit will not start

Possible Causes Corrective Action

4.9.3 Compressor cycles on low pressure control

4.9.4 Compressor cycles on high pressure control

4.0 MAINTENANCE (CONT.) ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

4.9 Troubleshooting Guide

74

4.10 Sample Log Sheet

ACDS-B / AUDS-B 015S to 100DReciprocating Compressor Packaged Chiller or Condensing Unit

NAMEPLATE DATA:

UNIT MODEL NO. UNIT SERIAL NO.

UNIT ELECTRICAL DATA: VOLTS 3 PHASE HZ

COMPRESSOR MODEL NO. COMPRESSOR S.N.



START UP: DATE , TIME

REPORT DATE

REPORT TIME

ELAPSED TIME METER COMPRESSOR 1



COOLER WATER TEMPERATURE - IN

COOLER WATER TEMPERATURE - OUT

COOLER PRESSURE DROP PSI/IN WATER

COOLER WATER FLOW (GPM)

CONDENSER AIR TEMPERATURE - IN (AMBIENT)

ACTUAL VOLTAGE

FAN AMPS

VOLTS

*Use Table 4.11 For Obtaining Saturated Temperature

This log sheet is provided as a recommendation of the readings that should be taken on a periodic basis. The actual readingstaken and the frequency will depend upon the unit’s applications, hours of use, etc. This type of information can prove veryuseful in preventing and/or solving problems that might occur during the life of this unit.

Sheet No.

Page 1 of 2


75

4.10 Sample Log Sheet

ACDS-B 015S-030SReciprocating Compressor Packaged Chiller

Sheet No.

Page 2 of 2

COMPR.

NO.

1

SUCTION PRESSURE 2

3

1

DISCHARGE PRESSURE 2

3

1

DISCHARGE TEMPERATURE 2

3

1

SUCTION TEMPERATURE 2

3

1

DISCHARGE SUPERHEAT 2(DISCH. TEMP. — SAT. DISCH.)*

3

1

SUCTION SUPERHEAT 2(SUCT. TEMP. — SAT. SUCT.)*

3

1

COMPRESSOR AMPS 2

3



PRES TEMP PRES TEMP PRES TEMP PRES TEMP PRES TEMP PRES TEMP

0 -41.4 55 30.1 110 64.4 165 88.6 220 108.0 276 124.5 1 -38.8 56 30.9 111 64.9 166 89.0 221 108.3 278 125.1 2 -36.4 57 31.7 112 65.4 167 89.4 222 108.6 280 125.6 3 -34.1 58 32.4 113 65.9 168 89.8 223 109.0 282 126.1 4 -31.8 59 33.2 114 66.4 169 90.2 224 109.3 284 126.7 5 -29.7 60 33.9 115 66.9 170 90.6 225 109.6 286 127.2 6 -27.7 61 34.7 116 67.4 171 91.0 226 109.9 288 127.7 7 -25.7 62 35.4 117 67.9 172 91.3 227 110.2 290 128.3 8 -23.8 63 36.1 118 68.3 173 91.7 228 110.5 292 128.8 9 -22.0 64 36.9 119 68.8 174 92.1 229 110.8 294 129.310 -20.2 65 37.6 120 69.3 175 92.5 230 111.2 296 129.811 -18.5 66 38.3 121 69.8 176 92.8 231 111.5 298 130.312 -16.9 67 39.0 122 70.2 177 93.2 232 111.8 300 130.913 -15.3 68 39.7 123 70.7 178 93.6 233 112.1 302 131.414 -13.7 69 40.4 124 71.2 179 93.9 234 112.4 304 131.915 -12.2 70 41.0 125 71.7 180 94.3 235 112.7 306 132.416 -10.7 71 41.7 126 72.1 181 94.7 236 113.0 308 132.917 -9.2 72 42.4 127 72.6 182 95.0 237 113.3 310 133.418 -7.8 73 43.0 128 73.0 183 95.4 238 113.6 312 133.919 -6.4 74 43.7 129 73.5 184 95.8 239 113.9 314 134.420 -5.1 75 44.3 130 74.0 185 96.1 240 114.2 316 134.921 -3.8 76 45.0 131 74.4 186 96.5 241 114.5 318 135.422 -2.5 77 45.6 132 74.9 187 96.9 242 114.8 320 135.923 -1.2 78 46.3 133 75.3 188 97.2 243 115.1 322 136.424 0.0 79 46.9 134 75.8 189 97.6 244 115.4 324 136.825 1.2 80 47.5 135 76.2 190 97.9 245 115.7 326 137.326 2.4 81 48.1 136 76.6 191 98.3 246 116.0 328 137.827 3.6 82 48.7 137 77.1 192 98.6 247 116.3 330 138.328 4.8 83 49.4 138 77.5 193 99.0 248 116.6 332 138.829 5.9 84 50.0 139 78.0 194 99.3 249 116.9 334 139.230 7.0 85 50.6 140 78.4 195 99.7 250 117.2 336 139.731 8.1 86 51.2 141 78.8 196 100.0 251 117.5 338 140.232 9.2 87 51.7 142 79.3 197 100.4 252 117.8 340 140.733 10.2 88 52.3 143 79.7 198 100.7 253 118.1 342 141.134 11.3 89 52.9 144 80.1 199 101.1 254 118.3 344 141.635 12.3 90 53.5 145 80.5 200 101.4 255 118.6 346 142.136 13.3 91 54.1 146 81.0 201 101.7 256 118.9 348 142.537 14.3 92 54.6 147 81.4 202 102.1 257 119.2 350 143.038 15.3 93 55.2 148 81.8 203 102.4 258 119.5 352 143.439 16.2 94 55.8 149 82.2 204 102.8 259 119.8 354 143.940 17.2 95 56.3 150 82.6 205 103.1 260 120.1 356 144.341 18.1 96 56.9 151 83.0 206 103.4 261 120.3 358 144.842 19.1 97 57.5 152 83.4 207 103.8 262 120.6 360 145.243 20.0 98 58.0 153 83.9 208 104.1 263 120.9 362 143.744 20.9 99 58.6 154 84.3 209 104.4 264 121.2 364 146.145 21.8 100 59.1 155 84.7 210 104.8 265 121.5 366 146.646 22.6 101 59.7 156 85.1 211 105.1 266 121.8 368 147.047 23.5 102 60.3 157 85.5 212 105.4 267 122.0 370 147.548 24.4 103 90.8 158 85.9 213 105.7 268 122.3 372 147.949 25.2 104 61.3 159 86.3 214 106.1 269 122.6 374 148.350 26.1 105 61.8 160 86.7 215 106.4 270 122.9 376 148.851 26.9 106 62.4 161 87.1 216 106.7 271 123.1 378 149.252 27.7 107 62.9 162 87.5 217 107.0 272 123.4 380 149.653 28.5 108 63.4 163 87.9 218 107.4 273 123.754 29.3 109 63.9 164 88.3 219 107.7 274 124.0

4.11 Temperature Pressure Table

Refrigerant 22 Pressure/Temperature Properties (PSIG-°F)

76

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